Barcelona and Real Madrid comprise el Clasico, one of the biggest and oldest rivalries in the footballing universe. Like all good rivalries it is contentious, entertaining and full of passion, but what sets it apart from the crowd is the sheer size of what's at stake. Their games often decide league titles; their results often decide their seasons. There's more than just bragging rights at play. We sized up their likely starting XIs and key subs to give you a look inside this storied match. We even tried to predict the outcome based on how these teams stack up. Game on.

Signed to replace the released Victor Valdes, the Chilean has sustained his fine World Cup form. Sharp reflexes and assertiveness mask any shot-stopping weaknesses.

AGE: 31 • KEY STAT: Has yet to concede a goal in La Liga this season (743 minutes, a record) • TRANSFER FEE: €12M ($15.3M), 2014

One of Spain's all-time great goalkeepers endured a long season of playing second fiddle to Diego Lopez last season. Some memorable recent errors hint at his decline. Can he hold firm?

AGE: 33 • KEY STAT: This will be his 35th Clasico • TRANSFER FEE: N/A (academy product)

Casillas will be remembered as an all-time great but he's steadily declining and can count himself extremely fortunate to be Real's current No. 1. By contrast, Bravo is relatively unheralded but is a fine sweeper-keeper, though less likely to make incredible saves. Casillas has had the better career but, on current form, you'd rather have Bravo between the posts.

What to watch: Burst onto the scene as a counterattacking full-back always eager to overlap and provide width. Lacks assertiveness against more physical teams.

AGE: 25 • KEY STAT: Averaged 1.2 key passes per league game in 2013-14 and had two assists • TRANSFER FEE: €14M ($17.9M), 2012

Highly touted right-back brought back to the Bernabeu after developing at Bayer Leverkusen. Solid, quick-thinking and confident on both sides of the ball.

A solid one-on-one defender, has been slowed by injuries in recent seasons but remains the anchor at the back. Superb passing range makes him useful in starting attacks.

Young French defender who has risen sharply since Jose Mourinho recruited him in 2011. Serene, calming influence beyond his years.

AGE: 21 • KEY STAT: In contrast to Ramos, Varane has fewer yellow cards (three) than trophies (five) at RM • TRANSFER FEE: €10M ($12.8M), 2011

Converted midfielder after various injury issues in central defense. Brings tenacity, organization and vision to the Barca back line.

Imposing and physical, Ramos sets the tone and tenor of Real's defensive play. Prone to own goals and red cards but atones with forceful aerial presence on set pieces.

AGE: 28 • KEY STAT: Of his 19 red cards for Real Madrid, three have come vs. Barcelona • TRANSFER FEE: €27M ($34.6M), 2005

The cornerstone of Barca's speedy counterattack, Alves provides indefatigable energy and passion from his full-back perch. He's lost a step in recent years but remains a credible threat.

AGE: 31 • KEY STAT: Has assisted more Lionel Messi goals (37) than any other player • TRANSFER FEE: €35.5M ($45.3M), 2008

Aggressive, feisty and rarely afraid of confrontation, the Brazilian left-back is at ease agitating Barcelona's front three. Loves to take on his opposite man on the dribble, but weak in the air.

AGE: 26 • KEY STAT: Had 6 assists in La Liga in 2013-14 ... the most of any defender. • TRANSFER FEE: €6.5M ($8.3M), 2007

Barcelona's individuals have seen better days but while Real's players possess more talent, Barca currently boast the better unit. They are rarely drawn out of shape, they don't concede as much space in behind as under previous regimes and they barely allow the opposition any chances. Seven games, no goals conceded, and therefore no question about the better defence.

Synonymous with tiki-taka and comfortable either in central midfield or wide attack in support of Messi, the combative playmaker is a valuable asset for Luis Enrique.

AGE: 30 • KEY STAT: Barca (45-5-0) and Spain (10-1-0) have yet to lose a game in which Iniesta has scored • TRANSFER FEE: N/A (academy product)

Intelligent, sharp and tireless, the German arrived this summer to solve Real's lack of depth in midfield. Very technical on the ball, capable of sitting deep or pushing up to start attacks.

AGE: 24 • KEY STAT: 2nd in the Bundesliga in passes completed with 2048 • TRANSFER FEE: €30M ($38.3M), 2014

The enforcer in the heart of midfield. Fans may not always like his disruptive, occasionally dirty style of play, but it is vital in Barca's pursuit of possession. He's quite composed on the ball, too.

Endlessly creative, Modric is the metronome around which Real operate. Sets the tempo and dictates the play with his passing. Lacks the strength to play effectively in defensive midfield.

AGE: 29 • KEY STAT: Ranked 4th on Madrid in chances created with 50 ... more than both Ronaldo (48) and Bale (40) • TRANSFER FEE: €30M ($38.3M), 2012

New arrival from Sevilla is the assumed heir to Xavi's throne as the main creator in midfield. Lacks the artistry of the Barca great but has served a valuable two-way role so far this season.

AGE: 26 • KEY STAT: One of only 5 players in La Liga in 2013-14 to reach double digits in both goals (12) and assists (10). Messi, Alexis Sanchez, Bale and Vela were the others. • TRANSFER FEE: €18M ($23M), 2014

In the absence of Gareth Bale, should be afforded the opportunity to push forward into the role that saw him lead the World Cup in scoring with six goals. A tireless worker who can link midfield and attack and play wide or narrow.

For the past five years Barca had the best midfield in the world. But Iniesta has been out of form, Busquets has encountered some nervous moments and Rakitic doesn't control games like Xavi. Kroos and Modric are intelligent enough to play deep effectively, but without a true holding midfielder, they could struggle against Messi's movement. Barcelona -- just about -- still edge this zone.

Maturing nicely at Barcelona, boasts plenty of quality and scoring prowess yet at ease being the second fiddle to Messi or any teammate in a better position.

AGE: 22 • KEY STAT: Already Brazil's fifth-highest scorer of all time (40 in 58 games) • TRANSFER FEE: €57.1M ($73M), 2013

An elegant playmaker who offers a contrast to the bombast and direct running of James. Lacks the requisite work rate of Modric or Kroos but has shone previously in big games, such as the 2014 Copa del Rey final.

AGE: 22 • KEY STAT: Created 70 chances for RM in 32 La Liga games last season, eighth best overall • TRANSFER FEE: €30M ($38.3M), 2013

Has adjusted to a better-rounded role in 2014, free of the burden to be Barca's creator and finisher. Pace, vision, agility, finishing (with either foot): the total package.

Often criticized for his "lack" of goals compared to Bale and Ronaldo, the Frenchman is the perfect foil in Real's attack. Off-the-ball movement opens room for teammates, while his finishing remains valuable.

AGE: 26 • KEY STAT: Assisted 24 goals for Ronaldo, second most since the Portuguese star arrived • TRANSFER FEE: €35M ($44.7M), 2009

How will he fare after a four-month suspension from competitive football? His temper is offset by a relentless desire to win. Work rate (if fully fit) from the front should keep Real on the back foot.

AGE: 27 • KEY STAT: Scored more Premier League goals for Liverpool (31) in 2013-14 than Norwich City (28) • TRANSFER FEE: €81M ($103), 2014

Arguably the world's best player right now. Contributes plenty of goals -- he has 15 in seven league games so far this season -- and assists and is impossible to keep quiet.

AGE: 29 • KEY STAT: Scored in six straight Clasicos (seven goals) between the 2011-13 seasons • TRANSFER FEE: €94M ($120M), 2009

Messi, Neymar and Suarez could set records but have yet to play together. Real boast the two most expensive players in the world but are weakened if Bale misses the game. Benzema is talented but is not a consistent world-class performer, and it feels like Real are depending more upon Ronaldo than last season. Barca will likely field three top-class forwards, and Real only one, so Barca look stronger.

An effective, reliable foil to Messi up front. Comfortable in either wide attacking berth, his pace and off-the-ball runs make him valuable in breaking open stubborn opponents. Not the most reliable in front of goal.

The Mexican striker struggled to assert himself at Manchester United but the consummate goal poacher is the perfect catalyst should Real struggle in the second half.

AGE: 26 • KEY STAT: Has scored two goals from three shots on goal in all competitions this season • TRANSFER FEE: N/A (season-long loan)

The grand master of midfielders, Xavi epitomized and defined Barca's sharp, relentless style. Has lost form and pace as he's aged but his connection with Busquets and Iniesta make him an intriguing wild card here.

Signed to provide added ballast in defensive midfield, he has struggled to get regular playing time. A capable, conservative option should Real look to shut the game down.

AGE: 24 • KEY STAT: Was 3rd best on Madrid with a 72.4 aerial % (aerials won/aerial duels) in 2013-14 • TRANSFER FEE: €30M ($38.3M), 2013

The latest product of La Masia, Munir has been a catalyst off the bench playing wide in support of Messi. A speedy, clever player well-drilled in the Barca mode.

AGE: 19 • KEY STAT: Scored his first Barca goal 46 minutes into his debut (Aug. 24, 2014 vs. Elche) • TRANSFER FEE: N/A (academy product)

A steady two-way midfielder who is comfortable in possession and puts in the hard yards from a defensive point of view. Will add solidity to complement Madrid's flair.

AGE: 27 • KEY STAT: Missed World Cup final through injury and has made just two appearances as substitute this season. • TRANSFER FEE: €14M ($17.9M), 2010

The towering central defender was signed this summer ahead of Barca's transfer ban and featured prominently in a string of league clean sheets. An aggressive and experienced option.

AGE: 30 • KEY STAT: Led Valencia last season in interceptions with 80 and shots blocked with 20 . • TRANSFER FEE: €20M ($25.5M), 2014

The butt of many jokes given his overly physical (some might say comic) approach to defending, Pepe can comfortably harass, unnerve and unsettle Barca's attackers.

Barcelona have more reliability -- Xavi is still a midfield master and Pedro understands the system better than anyone, for example -- but, in terms of game changers, Real excel. Hernandez is one of the best supersubs around while Illarramendi often performs better from the bench. Pepe is an impact player because of his raw physicality and Khedira can boost energy levels.

Played in the Clasico for both clubs and defeated Real Madrid 2-0 as Celta Vigo manager in 2013-14, ending RM's La Liga chase.

Has won three European Cup/Champions Leagues as manager (2x Milan, 1x Real Madrid), two as player (AC Milan).

You can't argue with Luis Enrique's league record at Barcelona so far: seven wins, one draw, no goals conceded. He's a perfect fit for the club yet even he wouldn't put himself in a bracket alongside Carlo Ancelotti just yet. However, the Real boss' Ancelotti's league-winning record is relatively unspectacular even though he's unquestionably one of the giants of this era.

Real Madrid strengthened in the summer but the departures of Xabi Alonso and Angel Di Maria robbed them of players who helped provide balance in midfield. Barcelona, on the other hand, have retained a familiar structure and haven't yet enjoyed the benefit of their major arrival, Luis Suarez. Barcelona, therefore, appear the better side on paper, and even with Real enjoying home advantage in the season's first Clasico, I think the visitors will just edge to a 2-1 win.

El Clasico. More Than A Game

BY MICHAEL COX ILLUSTRATIONS BY ROBB HArskamp Barcelona and Real Madrid comprise el Clasico, one of the biggest and oldest rivalries in the footballing universe. Like all good rivalries it is contentious, entertaining and full of passion, but what sets it apart from the crowd is the sheer size of what's at stake. Their games often decide league titles; their results often decide their seasons. There's more than just bragging rights at play. We sized up their likely starting XIs and key subs to give you a look inside this storied match. And, with Michael Cox's help, we even tried to predict the outcome based on how these teams stack up. Game on.

Goalkeepers

Iker Casillas AGE: 33 TRANSFER FEE: N/A (academy product) KEY STAT: This will be his 35th Clasico One of Spain's all-time great goalkeepers endured a long season of playing second fiddle to Diego Lopez in 2013-14. Some memorable recent errors hint at his decline. Can he hold firm?

Claudio Bravo AGE: 31 KEY STAT: Has yet to concede a goal in La Liga this season (743 minutes, a record)

TRANSFER FEE: €12M ($15.3M), 2014 Signed to replace the released Victor Valdes, the Chilean has sustained his fine World Cup form. Sharp reflexes and assertiveness mask any shot-stopping weaknesses.

Advantage: Barcelona Casillas will be remembered as an all-time great but he's steadily declining and can count himself extremely fortunate to be Real's current No. 1. By contrast, Bravo is relatively unheralded but is a fine sweeper-keeper, though less likely to make incredible saves. Casillas has had the better career, but on current form, you'd rather have Bravo between the posts.

Defenders

Marcelo AGE: 26 KEY STAT: Had 6 assists in La Liga in 2013-14 ... the most of any defender. TRANSFER FEE: €6.5M ($8.3M), 2007 Aggressive, feisty and rarely afraid of confrontation, the Brazilian left-back is at ease agitating Barcelona's front three. Loves to take on his opposite man on the dribble but weak in the air.

Sergio Ramos AGE: 28 KEY STAT: Of his 19 red cards for Real Madrid, three have come vs. Barcelona TRANSFER FEE: €27M ($34.6M), 2005 : Imposing and physical, Ramos sets the tone and tenor of Real's defensive play. Prone to own goals and red cards but atones with forceful aerial presence on set pieces.

Raphael Varane AGE: 21 KEY STAT: In contrast to Ramos, Varane has fewer yellow cards (three) than trophies (five) at RM TRANSFER FEE: €10M ($12.8M), 2011 Young French defender who has risen sharply since Jose Mourinho recruited him in 2011. Serene, calming influence beyond his years.

Daniel Carvajal AGE: 22 KEY STAT: Committed 48 fouls in 31 La Liga games in 2013-14 TRANSFER FEE: €6.5M ($8.3M), 2013 Highly touted right-back brought back to the Bernabeu after developing at Bayer Leverkusen. Solid, quick-thinking and confident on both sides of the ball.

Dani Alves AGE: 31 KEY STAT: Has assisted more Lionel Messi goals (37) than any other player TRANSFER FEE: €35.5M ($45.3M), 2008 The cornerstone of Barca's speedy counterattack, Alves provides indefatigable energy and passion from his full-back perch. He's lost a step in recent years but remains a credible threat.

Javier Mascherano AGE: 30 KEY STAT: 82 interceptions in 2013-14 La Liga TRANSFER FEE: €20M ($25.5M), 2010 Converted midfielder after various injury issues in central defense. Brings tenacity, organization and vision to the Barca back line.

Gerard Pique AGE: 27 KEY STAT: Completed 90% of his passes in La Liga, 2013-14 TRANSFER FEE: €5M ($6.4M), 2008 A solid one-on-one defender, has been slowed by injuries in recent seasons but remains the anchor at the back. Superb passing range makes him useful in starting attacks.

Jordi Alba AGE: 25 KEY STAT: Averaged 1.2 key passes per league game in 2013-14 and had two assists TRANSFER FEE: €14M ($17.9M), 2012 Burst onto the scene as a counterattacking full-back always eager to overlap and provide width. Lacks assertiveness against more physical teams.

Advantage: Barcelona Barcelona's individuals have seen better days but while Real's players possess more talent, Barca currently boast the better unit. They are rarely drawn out of shape, they don't concede as much space in behind as under previous regimes and they barely allow the opposition any chances. Seven games, no goals conceded, and therefore no question about the better defence.

Midfielders

James Rodriguez AGE: 23 KEY STAT: Created 84 chances in Ligue 1, 2013-14. Bale/Ronaldo created 88 combined in La Liga TRANSFER FEE: €80M ($102.2M), 2014 In the absence of Gareth Bale should be afforded the opportunity to push forward into the role that saw him lead the World Cup in scoring with six goals. A tireless worker who can link midfield and attack and play wide or narrow.

Luka Modric AGE: 29 KEY STAT: Ranked 4th on Madrid in chances created with 50 ... more than both Ronaldo (48) and Bale (40) TRANSFER FEE: €30M ($38.3M), 2012 Endlessly creative, Modric is the metronome around which Real operate. Sets the tempo and dictates the play with his passing. Lacks the strength to play effectively in defensive midfield.

Toni Kroos AGE: 24 KEY STAT: 2nd in the Bundesliga in passes completed with 2048 TRANSFER FEE: €30M ($38.3M), 2014 Intelligent, sharp and tireless, the German arrived this summer to solve Real's lack of depth in midfield. Very technical on the ball, capable of sitting deep or pushing up to start attacks.

Ivan Rakitic AGE: 26 KEY STAT: One of only 5 players in La Liga in 2013-14 to reach double digits in both goals (12) and assists (10). Messi, Alexis Sanchez, Bale and Vela were the others. TRANSFER FEE: €18M ($23M), 2014 New arrival from Sevilla is the assumed heir to Xavi's throne as the main creator in midfield. Lacks the artistry of the Barca great but has served a valuable two-way role so far this season.

Sergio Busquets AGE: 26 KEY STAT: Led La Liga in 2013-14 with 92.4% passing accuracy (min. 100 passes) TRANSFER FEE: N/A (academy product) The enforcer in the heart of midfield. Fans may not always like his disruptive, occasionally dirty style of play but it is vital in Barca's pursuit of possession. He's quite composed on the ball, too.

Andres Iniesta AGE: 30 KEY STAT: Barca (45-5-0) and Spain (10-1-0) have yet to lose a game in which Iniesta has scored TRANSFER FEE: N/A (academy product) Synonymous with tiki-taka and comfortable either in central midfield or wide attack in support of Messi, the combative playmaker is a valuable asset for Luis Enrique.

Advantage: Barcelona For the past five years Barca had the best midfield in the world. But Iniesta has been out of form, Busquets has encountered some nervous moments and Rakitic doesn't control games like Xavi. Kroos and Modric are intelligent enough to play deep effectively, but without a true holding midfielder, they could struggle against Messi's movement. Barcelona -- just about -- still edge this zone.

Forwards

Cristiano Ronaldo AGE: 29 KEY STAT: Scored in six straight Clasicos (seven goals) between the 2011-13 seasons TRANSFER FEE: €94M ($120M), 2009 Arguably the world's best player right now. Contributes plenty of goals -- he has 15 in seven league games so far this season -- and assists and is impossible to keep quiet.

Karim Benzema AGE: 26 KEY STAT: Assisted 24 goals for Ronaldo, second most since the Portuguese star arrived TRANSFER FEE: €35M ($44.7M), 2009 Often criticized for his "lack" of goals compared to Bale and Ronaldo, the Frenchman is the perfect foil in Real's attack. Off-the-ball movement opens room for teammates, while his finishing remains valuable.

Isco AGE: 22 KEY STAT: Created 70 chances for RM in 32 La Liga games last season, eighth-best overall TRANSFER FEE: €30M ($38.3M), 2013 An elegant playmaker who offers a contrast to the bombast and direct running of James. Lacks the requisite work rate of Modric or Kroos but has shone previously in big games, such as the 2014 Copa del Rey final.

Luis Suarez AGE: 27 KEY STAT: Scored more Premier League goals for Liverpool (31) in 2013-14 than Norwich City (28) TRANSFER FEE: €81M ($103), 2014 How will he fare after a four-month suspension from competitive football? His temper is offset by a relentless desire to win. Work rate (if fully fit) from the front should keep Real on the back foot.

Lionel Messi AGE: 27 KEY STAT: Leads all players with 21 goals in Clasicos TRANSFER FEE: N/A (academy product) Has adjusted to a better-rounded role in 2014, free of the burden to be Barca's creator and finisher. Pace, vision, agility, finishing (with either foot): the total package.

Neymar AGE: 22 KEY STAT: Already Brazil's fifth-highest scorer of all time (40 in 58 games)

TRANSFER FEE: €57.1M ($73M), 2013 Maturing nicely at Barcelona, boasts plenty of quality and scoring prowess yet at ease being the second fiddle to Messi or any teammate in a better position.

Advantage: Barcelona Messi, Neymar and Suarez could set records but have yet to play together. Real boast the two most expensive players in the world but are weakened if Bale misses the game. Benzema is talented but is not a consistent world-class performer, and it feels like Real are depending more upon Ronaldo than last season. Barca will likely field three top-class forwards, and Real only one, so Barca look stronger.

Substitutes

Pepe AGE: 31 KEY STAT: Blocked 25 shots in 2013-14 La Liga season, eighth best overall

TRANSFER FEE: €30M ($38.3M), 2007 The butt of many jokes given his overly physical (some might say comic) approach to defending, Pepe can comfortably harass, unnerve and unsettle Barca's attackers.

Sami Khedira AGE: 27 KEY STAT: Missed World Cup final through injury and has made just two appearances as substitute this season. TRANSFER FEE: €14M ($17.9M), 2010 A steady two-way midfielder who is comfortable in possession and puts in the hard yards from a defensive point of view. Will add solidity to complement Madrid's flair.

Asier Illarramendi AGE: 24 KEY STAT: Was 3rd best on Madrid with a 72.4 aerial % (aerials won/aerial duels) in 2013-14 TRANSFER FEE: €30M ($38.3M), 2013 Signed to provide added ballast in defensive midfield, he has struggled to get regular playing time. A capable, conservative option should Real look to shut the game down.

Chicharito Hernandez AGE: 26 KEY STAT: Has scored two goals from three shots on goal in all competitions this season TRANSFER FEE: N/A (season-long loan) The Mexican striker struggled to assert himself at Manchester United, but the consummate goal-poacher is the perfect catalyst should Real struggle in the second half.

Jeremy Mathieu AGE: 30 KEY STAT: Led Valencia last season in interceptions with 80 and shots blocked with 20. TRANSFER FEE: €20M ($25.5M), 2014 The towering central defender was signed this summer ahead of Barca's transfer ban and featured prominently in a string of league clean sheets. An aggressive and experienced option.

Munir El Haddadi AGE: 19 KEY STAT: Scored his first Barca goal 46 minutes into his debut (Aug. 24, 2014 vs. Elche)

TRANSFER FEE: N/A (academy product) The latest product of La Masia, Munir has been a catalyst off the bench playing wide in support of Messi. A speedy, clever player well-drilled in the Barca mode.

Xavi AGE: 34 KEY STAT: Leads all active players with 40 Clasico appearances TRANSFER FEE: N/A (academy product) The grand master of midfielders, Xavi epitomized and defined Barca's sharp, relentless style. Has lost form and pace as he's aged but his connection with Busquets and Iniesta make him an intriguing wild card here.

Pedro Rodriguez AGE: 27 KEY STAT: 19 goals, 8 assists in all competitions in 2013-14 TRANSFER FEE: N/A (academy product) An effective, reliable foil to Messi up front. Comfortable in either wide attacking berth, his pace and off-the-ball runs make him valuable in breaking open stubborn opponents. Not the most reliable in front of goal.

Advantage: Real Madrid Barcelona have more reliability -- Xavi is still a midfield master, and Pedro understands the system better than anyone, for example -- but in terms of game-changers, Real excel. Hernandez is one of the best supersubs around, while Illarramendi often performs better from the bench. Pepe is an impact player because of his raw physicality, and Khedira can boost energy levels.

Managers

Carlo Ancelotti AGE: 55 Salary: €7.5M per year ($9.6M, estimated) Biggest achievements: Has won three European Cup/Champions Leagues as manager (2x Milan, 1x Real Madrid), two as player (AC Milan).

Luis Enrique AGE: 44 Salary: unknown Biggest achievement: Played in the Clasico for both clubs and defeated Real Madrid 2-0 as Celta Vigo manager in 2013-14, ending RM's La Liga chase.

Advantage: Real Madrid You can't argue with Luis Enrique's league record at Barcelona so far: seven wins, one draw, no goals conceded. He's a perfect fit for the club, yet even he wouldn't put himself in a bracket alongside Carlo Ancelotti just yet. However, Ancelotti's league-winning record is relatively unspectacular even though he's unquestionably one of the giants of this era.

Who Will Win?