(CNN) Rejected by his hometown club for being too small and a career hindered by a succession of serious injuries.

Say what you like about Marco Reus but when it comes to resilience he's got very few peers.

Despite his undeniable talent, adversity has come to define the forward's career and hampered his progression to the very top.

"If Marco [Reus] didn't have any injuries, he would be one of the top players in football" Bundesliga expert and former professional Lutz Pfannenstiel told CNN Sport.

Marco Reus has been in impressive form this season, scoring 12 goals for Dortmund.

However, since returning from a miserable World Cup campaign with Germany, Reus has been in electric form.

He's scored 12 times in 21 appearances for his club -- a record which has inspired Borussia Dortmund to the summit of both the Bundesliga and their Champions League group.

Injury nightmare

Reus' quality has never been in question though. The pacy attacker combines a clinical edge to his creative flair, making him one of the world's most potent threats in the game.

But such praise comes with a caveat.

The 29-year-old has battled with injuries throughout his career, a trait which has reared its ugly head at some of the most important moments of his career.

Reus was forced to miss Germany's successful World Cup campaign in 2014.

Notably, an in-form Reus was forced to miss Germany's successful World Cup campaign in 2014 after sustaining an ankle injury just weeks before the start of tournament.

In 2017, Reus then suffered cruciate ligament damage and missed eight months of action -- many doubted the player would ever return to his best.

However, it appears the German has learned from his frustrating spell on the sidelines and has developed a better understanding of his body.

"I think now he's reached the point where he knows a little bit more about himself and how to look after his body," said Pfannenstiel.

'Beast' mentality

Injuries may have physically prevented Reus from fulfilling his frightening potential but they have "made him mentally into an absolute beast," said Pfannenstiel, who believes missing the 2014 World Cup still plays on Reus' mind.

"He is always getting knocked down in the most important part of his career and he's always managed to come back."

Having joined his beloved Dortmund's youth academy, Reus was told he was too weak to make it as a professional at the top level.

As a result, he reluctantly took a step down to pursue his passion, initially joining Rot Weiss Ahlen in 2006 before making his name at Borussia Mönchengladbach three years later.

His performances for Mönchengladbach cemented himself as one of the best attacking players in the division, in doing so attracting the attention of his former club.

After being dropped by Dortmund, Reus made his name at Borussia Moenchengladbach.

He returned to where it all began in 2012 and it was almost the perfect return.

Led by Jurgen Klopp and fronted by the threat of Reus, Dortmund reached the final of the Champions League in 2013. Frustratingly, their dream was ended by bitter rivals Bayern Munich.

Despite the obvious disappointment, Reus' inclusion in the final came exactly six years after being rejected by the club, demonstrating the resilience shown throughout his career.

"Being rejected gave him that motivation to become the player he is," said Pfannenstiel, who has met Reus a number of times throughout his career.

"It's one of the football fairytales. Being small and being rejected and then coming back to be a national player and now the captain."

Reus returned to Borussia Dortmund in 2012.

Captain's role

Perhaps the secret to his recent success lies in the club's decision to hand Reus the captaincy, giving him added responsibility on and off the pitch.

"He's now not just one of the players, he's a guy that other players look up to as a role model. I think it was a clever move by the club," said Pfannenstiel.

Reus is not a natural born leader though, nor is he your typical football player. The German is calm, quiet and modest about his undeniable talent.

He tends to stay away from controversy and instead prefers to concentrate on his own brand, MRXI, and supporting a multitude of children charities.

"He won't be a Lothar Matthaus or a Stuart Pearce, one of those typical leading players," Pfannenstiel admitted.

"He's more of a role model through his performances on the pitch, where he can pull people with him and make players better around him."

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Role model

His form this season comes as little surprise to his teammates though, who have had the pleasure of seeing his ability in training every day.

"I've always known what he's been capable of doing, it doesn't surprise me. We know what a great player he is, what a great finisher he is," said Borussia Dortmund youngster Christian Pulisic.

"We're happy for him, he's playing well and scoring goals and that's what he loves to do."

Pulisic is part of a new generation coming through at Dortmund, along with the likes of former Manchester City starlet Jadon Sancho.

Both are now in the best place to learn from Reus and benefit from his rich wealth of experience in the Bundesliga.

"His composure on the field is incredible. How calm he is, how clinical he is. It's a lot you can learn from him for sure," said the 20-year-old Pulisic.

Reus knows just how important a good role model is when starting a career.

He idolized former Arsenal and Czech Republic midfielder Tomas Rosicky as a youngster, copying elements of his graceful attacking prowess.

Reus has inspired Dortmund to the top of the Bundesliga and their Champions League group.

World class?

It's all seemed to click into place for Reus now.

The game plan introduced by Lucien Favre at Dortmund has suited him and he looks to have matured into his position.

A sustained run of form could finally cement the forward among the world's elite but a place alongside the very best is perhaps out of reach.

"Getting to the level of Ronaldo, Messi, and Modric is a really tough cookie to crack," Pfannenstiel said.

"You need to be injury-free, you need to be six or seven years in the top Champions League club to achieve that level."

Photos: Best atmospheres in world football Borussia Dortmund – Borussia's Dortmund's Westfalenstadion Stadium is known for its "Yellow Wall." The south stand is packed full of impassioned fans who together create one of the most spell-binding sights in football. Dressed in the team's yellow and black, supporters create an intimidating atmosphere for the opposition. Hide Caption 1 of 8 Photos: Best atmospheres in world football Liverpool – There is something special about Anfield on a European night and the stadium's Spion Kop seems to drag the ball into the goal when Liverpool are attacking that end. Fans also sing the stirring "You'll Never Walk Alone" before every match to create a spine-tingling spectacle. Hide Caption 2 of 8 Photos: Best atmospheres in world football Galatasaray – The Turk Telekom Stadium is home to Turkish giants Galatasaray. The fans here don't just wait for the big games to create an atmosphere. The stadium -- which is the second biggest in the country with a capacity of 52,223 -- is always awash with flags, scarves and flares. Hide Caption 3 of 8 Photos: Best atmospheres in world football Napoli – The Stadio San Paolo has one of the most raucous atmospheres in Serie A. Large flags and constant singing are common place in Naples, making this iconic stadium rock during home matches. Hide Caption 4 of 8 Photos: Best atmospheres in world football Roma – The Stadio Olimpico in Rome is a gladiatorial like venue. With a capacity of 72,698, the stadium is home to both Roma and Lazio. The fiery atmosphere is magnified by the traditional surroundings which helps produce a caldron of noise. Hide Caption 5 of 8 Photos: Best atmospheres in world football Sevilla – With a capacity of 43,883, the Ramon Sanchez Pizjuan cannot compare to the size of some stadiums in La Liga but its atmosphere can. The home fans are a big factor behind Sevilla's impressive home-record. The team went over a year without a loss at home in 2017. Hide Caption 6 of 8 Photos: Best atmospheres in world football Boca Juniors – La Bombonera is the home to Argentine side Boca Juniors. The fans are at most vocal for the Buenos Aires derby against River Plate where both sets of supporters combine to make a carnival like atmosphere. It may only have capacity of 49,000, but the tight surroundings make for an electric wall of noise. Hide Caption 7 of 8 Photos: Best atmospheres in world football Red Star Belgrade – The Rajko Mitic Stadium in Serbia can be one of the most intimidating places to play football. Fans create huge banners in support of the team and frequently use pyrotechnics to intimidate the opposition. Hide Caption 8 of 8

Led by Reus, Dortmund have already qualified for the knockout stages of the Champions League this season.

A win against Monaco on Tuesday could see them move top of Group A.