Brad Edwards crunches the numbers behind J.T. Barrett's efficiency through the years and explains why other OSU playmakers will need to step up this season. (1:31)

The Big Ten features a pair of national title contenders in No. 2 Ohio State and defending league champ No. 6 Penn State. And No. 9 Wisconsin and No. 11 Michigan could play their way into the playoff discussion as well. The Big Ten is deep and talented, and will once again make its case that it belongs in any discussion for the best conference in the country.

ILLINOIS FIGHTING ILLINI

Last year’s record: 3-9 overall (2-7 in the Big Ten)

Key returning players: RB Kendrick Foster, WR Malik Turner, LB Tre Watson, SS Patrick Nelson, WR Mike Dudek

Key losses: LB Hardy Nickerson Jr., DL Carroll Phillips, DL Dawuane Smoot, QB Wes Lunt

Reason for optimism: Running back Kendrick Foster might be one of the most under-heralded players in the Big Ten when it comes to big-play ability and versatility. Foster forced his way into a starting role last season, averaging 5.7 yards per carry and collecting seven touchdowns. He and Reggie Corbin give the Illini a solid duo of backs to build around. The question will be whether a young offensive line can give them space to operate.

Cause for concern: Lovie Smith's defense allowed a worrisome 219 rushing yards per game in 2016, and now it has to replace four veterans (including a couple who went off to the NFL) with a young, inexperienced crop of defensive linemen. The entire roster is young, but if Illinois can't hold its own along the line of scrimmage, it will be tough to improve on last year's struggles.

X factor: Mike Dudek's return after back-to-back ACL tears could be a boon for roommate and QB Chayce Crouch. If Dudek returns to his freshman form (76 catches, 1,038 yards), he and Malik Turner could be the West Division's most dangerous receiver duo this season. However, Dudek will need to prove his durability and that he hasn't lost a step after two devastating setbacks.

Game to watch: Sept. 15 at South Florida

-- Dan Murphy

INDIANA HOOSIERS

Last year’s record: 6-7 (4-5)

Key returning players: QB Richard Lagow, WR Nick Westbrook, WR Simmie Cobbs Jr., LB Tegray Scales, DB Rashard Fant

Key losses: RB Devine Redding, WR Ricky Jones, WR Mitchell Paige, LB Marcus Oliver, OL Wes Rogers, OL Dan Feeney

Reason for optimism: Tom Allen helped Indiana's defense go from abysmal to respectable in one season as defensive coordinator. The Hoosiers were No. 45 in yards per game and No. 26 in yards per play on defense. Now the head coach, Allen is still manning the defense, which is good news for a Hoosiers unit that looks to build on last season's success.

Cause for concern: What's going to happen to the offense? Coach Kevin Wilson was dismissed by the school in December after alleged player mistreatment. He was the mastermind behind Indiana's offense and a big part of the optimism about where the program was heading on the field. There are questions as to whether new offensive coordinator Mike Debord can produce the same results as Wilson and if that success can be sustained once quarterback Richard Lagow is gone.

X factor: Linebacker Tegray Scales could put together a dominant season for this defense. A preseason ESPN All-American, Scales led the Big Ten in tackles last season. If he improves on those stats somehow, the defense, with nine returning starters, could take a big step forward.

Game to watch: Aug. 31 vs. Ohio State

-- Tom VanHaaren

IOWA HAWKEYES

Last year’s record: 8-5 (6-3)

Key returning players: LB Josey Jewell, OL Sean Welsh, RB Akrum Wadley, WR Matt VandeBerg, LB Bo Bower

Key losses: QB C.J. Beathard, CB Desmond King, RB LeShun Daniels, DT Jaleel Johnson

Reason for optimism: Iowa is stocked well to do what it does best. The offensive line has nearly 100 career starts under its collective and sizable belt. Akrum Wadley returns to run behind them after topping 1,000 rushing yards last season. On defense, one of the league's best linebacker corps will make it difficult for opponents to grind out drives against the Hawkeyes.

Cause for concern: The passing game could struggle in 2017. The Hawkeyes picked sophomore Nathan Stanley over junior Tyler Wiegers at quarterback this week, although it doesn't appear Stanley distanced himself significantly from the competition. He'll be throwing to a group that returns only one wide receiver who made at least 10 catches last season.

X factor: Iowa's secondary isn't void of potential, but the back end will be without a former Thorpe Award winner (Desmond King) and a three-year starter (Greg Mabin) at the two cornerback spots. If they can slow down some of the Big Ten's better passing attacks, the Hawkeyes' defense should be good enough to keep the team competitive no matter whom they are facing. The young secondary gets thrown into the deep end (without suspended starter Manny Rugamba) in their season opener against Wyoming's star quarterback, Josh Allen.

Game to watch: Oct. 28 vs. Minnesota

-- Dan Murphy

MARYLAND TERRAPINS

Last year’s record: 6-7 (3-6)

Key returning players: RB Ty Johnson, RB Lorenzo Harrison, WR D.J. Moore, QB Tyrrell Pigrome, LB Jermaine Carter, LB Shane Cockerille, DB Darnell Savage, LB Jesse Aniebonam

Key losses: WR Teldrick Morgan, WR Levern Jacobs, DE Roman Braglio, DB Alvin Hill

Reason for optimism: The offense returns a lot of its production from last season and is heading into its second season with offensive coordinator Walt Bell. That side should continue to improve and help Maryland take a step forward in the win column.

Cause for concern: A schedule that just doesn't let up. The Terps have to play at Texas, then go on a midseason run playing at Ohio State, home against Northwestern and at Wisconsin before finishing with visits from Michigan and Penn State. That is a tough schedule to get through from start to finish.

X factor: Quarterback will be a huge part of how Maryland fares this season. Sophomore Tyrrell Pigrome beat out a sizable list of candidates to start the season opener against Texas. Touted freshman Kasim Hill is next behind Pigrome on the depth chart. If one of those guys proves to be a good fit for offensive coordinator Walt Bell's aggressive attack, the Terps will be headed in the right direction.

Game to watch: Sept. 30 at Minnesota

-- Tom VanHaaren

MICHIGAN WOLVERINES

Last year’s record: 10-3 (7-2)

Key returning players: QB Wilton Speight, RB Chris Evans, OL Mason Cole, OL Ben Bredeson, DE Rashan Gary, DT Maurice Hurst, DT Bryan Mone, DE Chase Winovich, LB Mike McCray

Key losses: RB De'Veon Smith, WR Amara Darboh, WR Jehu Chesson, TE Jake Butt, OL Erik Magnuson, OL Kyle Kalis, DE Taco Charlton, DE Chris Wormley, DT Ryan Glasgow, LB Ben Gedeon, LB Jabrill Peppers, DB Jourdan Lewis, DB Channing Stribling, DB Delano Hill

Reason for optimism: Michigan has the same defensive coordinator (Don Brown) for two seasons in a row for the first time since the 2013-14 seasons. The players have said that is a huge boost to their confidence and ability to retain the defense. On top of the familiarity, Jim Harbaugh and his staff have been recruiting at a very high level, which will allow the coaches to play plenty of freshmen this season.

Cause for concern: Michigan is the youngest FBS team this season, after it lost most of the defensive starters and some big pieces on offense. Having that much youth on the defense could mean the Wolverines need time to adjust and suffer some growing pains before they start to play at a high level.

X factor: Can Michigan’s first- and second-year players step up and fill big shoes? The Wolverines lost their top three offensive players in receiving yardage, so they will need Donovan Peoples-Jones and Tarik Black to step up on offense. On the other side of the ball, there are big expectations for defensive end Rashan Gary, a former No. 1 overall prospect.

Game to watch: Sept. 2 vs. Florida

-- Tom VanHaaren

MICHIGAN STATE SPARTANS

Last year’s record: 3-9 (1-8)

Key returning players: QB Brian Lewerke, RB LJ Scott, RB Gerald Holmes, LB Chris Frey, LB Andrew Dowell, DE Demetrius Cooper, DT Raequan Williams, DT Mike Panasiuk

Key losses: WR R.J. Shelton, TE Josiah Price, WR Monty Madaris, LB Riley Bullough, DB Darian Hicks, DB Montae Nicholson, DB Demetrious Cox

Reason for optimism: Maybe last season was a fluke and the players holding the Spartans back are now out of the locker room. Coach Mark Dantonio has been good at creating a chip on his players’ shoulders in the past and no doubt Dantonio is using last season as a giant motivational chip heading into this season.

Cause for concern: Michigan State’s defense has been declining since the departure of former defensive coordinator Pat Narduzzi after the 2014 season. The Spartans return only four defensive starters from a group that ranked 61st in scoring defense last season. Linebackers Chris Frey and Andrew Dowell provide some stability, but they will be breaking in some inexperienced players on a unit that needs help.

X factor: QB Brian Lewerke's success is going to be one of the most important aspects of Michigan State's season. Mark Dantonio has thrown out comparisons to Kirk Cousins and Connor Cook. If Lewerke lives up to that lofty praise, good things can happen for the offense.

Game to watch: Sept. 23 vs. Notre Dame

-- Tom VanHaaren

MINNESOTA GOLDEN GOPHERS

Last year’s record: 9-4 (5-4)

Key returning players: RB Rodney Smith, RB Shannon Brooks, LB Jonathan Celestin, LB Blake Cashman, WR Rashad Still

Key losses: QB Mitch Leidner, WR Drew Wolitarsky, DB Jalen Myrick, DB Damarius Travis

Reason for optimism: The college football world has yet to find the bottom of P.J. Fleck's well of infectious optimism. The new coach's unique brand of leadership helped build Western Michigan into a Group of 5 powerhouse. Now he starts over with a Gophers team that won nine games a season ago and returns some talented players in important places.

Cause for concern: Depth, especially in the trenches. The Gophers put together a solid pass rush (37 sacks) last season, but doing so again will require that they avoid the injury bug. Defensive tackle Steven Richardson provides a good anchor up front, but developing a rotation on the edges of the line will be a project to start the season. Losing two talented starters from the secondary also leaves that group without margin for injury.

X factor: Minnesota as a whole might be the Big Ten's most intriguing X-factor this season. The Gophers can make things interesting in the West, especially if they find a way to develop a passing game to go with two good running backs. Conor Rhoda and Demry Croft both will get a chance to win the quarterback job during the first couple of weeks of the season. Fleck, a former receiver himself, developed some good pass-catchers at Western Michigan. If Rashad Still can transform into a consistent playmaker this season, that would be a significant step in the right direction.

Game to watch: Sept. 30 vs. Maryland

-- Dan Murphy

NEBRASKA CORNHUSKERS

Last year’s record: 9-4 (6-3)

Key returning players: OL Nick Gates, RB Devine Ozigbo, WR De'Mornay Pierson-El, WR Stanley Morgan, DL Freedom Akinmoladun

Key losses: RB Terrell Newby, S Nate Gerry, LB Michael Rose-Ivey, QB Tommy Armstrong

Reason for optimism: Tanner Lee takes over the offense after transferring from Tulane. The strong-armed junior excited pro scouts this offseason and seems to be a more natural fit for the type of offense coach Mike Riley employed while at Oregon State. In Riley's third season, his staff has had the time to implement its playbook and is hoping to see an uptick from the 26.5 points per game they averaged last season.

Cause for concern: The Huskers are hitting the reset button on defense this year by switching to a 3-4 look under the direction of new coordinator Bob Diaco. Diaco's defense has had success (most notably during a run to a national title game at Notre Dame in 2012), but it might take a year or two to get the body types that best fill out his scheme.

X factor: Who will Lee target for most of 2017? Nebraska's staff has said De'Mornay Pierson-El and Stanley Morgan both are physically prepared to handle a bigger role after showing promising flashes as underclassmen. Freshman Tyjon Lindsey is another potential playmaker if he can get up to college speed quickly. If all three find their stride, the Cornhuskers could have a dangerous passing game, but all three still have to prove they are reliable options.

Game to watch: Sept. 9 at Oregon

-- Dan Murphy

NORTHWESTERN WILDCATS

Last year’s record: 7-6 (5-4)

Key returning players: RB Justin Jackson, S Godwin Igwebuike, QB Clayton Thorson, LB Nate Hall

Key losses: WR Austin Carr, LB Anthony Walker, WR Solomon Vault (injury), DL Ifeadi Odenigbo

Reason for optimism: Pat Fitzgerald's team returns eight starters on both sides of the ball, most notably the veteran backfield duo of Clayton Thorson and Justin Jackson. Jackson has a chance to set a school record for career yards, and Thorson should continue to develop as a dual threat in his third year as a starter.

Cause for concern: The front seven should be solid against the run, but they need to replace their three most dynamic pass-rushers from a year ago. Ifeadi Odenigbo is playing for the Vikings. Anthony Walker is a Colt. And Xavier Washington has been suspended from the program since the spring following a drug arrest. That trio combined for 16.5 of the team's 27 sacks last season -- production that will need to be replaced.

X factor: The one place where Northwestern is notably unseasoned on offense is at wide receiver. Austin Carr caught a conference-leading 90 passes as Thorson's clear favorite target a year ago. Without him, the Wildcats will need someone with less experience to emerge from the pack. Flynn Nagel (40 catches in 2016) and Oregon transfer Jalen Brown are the two best bets to step up. Their success in turning Northwestern into a two-dimensional offense will go a long way in determining the program's chances of winning the West.

Game to watch: Sept. 30 at Wisconsin

-- Dan Murphy

OHIO STATE BUCKEYES

Last year’s record: 11-2 (8-1)

Key returning players: QB J.T. Barrett, RB Mike Weber, OL Billy Price, OL Michael Jordan, WR Terry McLaurin, DE Sam Hubbard, DE Tyquan Lewis, DT Dre'Mont Jones, DT Tracy Sprinkle, LB Jerome Baker, LB Chris Worley

Key losses: HB Curtis Samuel, HB Dontre Wilson, WR Noah Brown, OL Pat Elflein, LB Raekwon McMillan, DB Gareon Conley, DB Malik Hooker, DB Marshon Lattimore

Reason for optimism: Urban Meyer has an outstanding defensive line returning and a defense that could be dominant this season. He also has new coordinator Kevin Wilson to boost the offense and revamp it to bring a little more production to a unit that brings back quite a bit from last season.

Cause for concern: There isn't much to be concerned about this season for Ohio State, but if Barrett can't improve his accuracy and adapt to Wilson's offense, it could hinder a unit that finished 31st in yards per game last season.

X factor: The Ohio State receivers. The passing game likely will be more prevalent in Wilson’s offense, and with Ohio State’s top three receivers -- Curtis Samuel, Noah Brown and Dontre Wilson -- off to the NFL, the new crop of receivers needs to make an immediate impact. Austin Mack, Johnnie Dixon and K.J. Hill, in particular, will be big factors this season.

Game to watch: Sept. 9 against Oklahoma

-- Tom VanHaaren

Trace McSorley and Saquon Barkley form what could be the best quarterback-running back tandem in the country. Rich Graessle/Icon Sportswire

PENN STATE NITTANY LIONS

Last year’s record: 11-3 (8-1)

Key returning players: QB Trace McSorley, RB Saquon Barkley, WR DaeSean Hamilton, WR DeAndre Thompkins, TE Mike Gesicki, DB Marcus Allen, LB Jason Cabinda

Key losses: WR Chris Godwin, LB Brandon Bell, DE Garrett Sickels, DE Evan Schwan, DB Malik Golden

Reason for optimism: Trace McSorley and Saquon Barkley form what could be the nation's best QB-RB tandem and lead an exciting and explosive offense that returns nine starters. The defense returns six starters as well from a unit that held its final seven regular-season opponents to just 21 points a game. There is a ton of optimism around the program heading into this season with some continuity at the coordinator positions and the players on the field.

Cause for concern: Chris Godwin had 11 receiving touchdowns for the Nittany Lions last season, but he is off to the NFL. Tight end Mike Gesicki had five, and no other receiver had more than one. If DaeSean Hamilton, Juwan Johnson and DeAndre Thompkins can’t fill in where Godwin left off, it could cause trouble for the offense.

X factor: Barkley is one of the best players in the country, and even after rushing for 1,496 yards and 18 TDs last season, expectations could be even bigger for him this season. If he can improve on what he did last season -- and that is a very realistic possibility -- he should be in the Heisman conversation.

Game to watch: Oct. 28 at Ohio State

-- Tom VanHaaren

PURDUE BOILERMAKERS

Last year’s record: 3-9 (1-8)

Key returning players: QB David Blough, RB Markell Jones, LB Ja'Whaun Bentley, DE Gelen Robinson

Key losses: DT Jake Replogle, WR DeAngelow Yancey, S Leroy Clark

Reason for optimism: A coaching change always brings new hope, and with Jeff Brohm it seems justified in West Lafayette. It might take more than one offseason for Brohm to fully install the offense that helped Western Kentucky lead the nation with 45.5 points per game, but the Boilermakers now have a staff that understands they need to be different to compete in the Big Ten. Quarterback David Blough and a couple of additions from the transfer market give Brohm some good initial ingredients with which to work.

Cause for concern: The offensive line was a concern throughout the tenure of former coach Darrell Hazell, and that hasn't changed in 2017. Depth and size up front both will have to improve for Purdue to be competitive in the Big Ten.

X factor: A solid linebackers group could help Purdue's defense take a step in the right direction if everyone stays healthy and jells. Western Kentucky transfer T.J. McCollum should help serve as a bridge for the new coaching staff. Ja'Whaun Bentley and Danny Ezechukwu both are capable of taking a leap forward after good showings last fall.

Game to watch: Nov. 4 vs. Illinois

-- Dan Murphy

RUTGERS SCARLET KNIGHTS

Last year’s record: 2-10 (0-9)

Key returning players: WR Janarion Grant, RB Robert Martin, RB Josh Hicks, WR Jawuan Harris, LB Trevor Morris, LB Deonte Roberts, DE Darnell Davis

Key losses: RB Justin Goodwin, WR Andre Patton, RB Justin Goodwin, DB Anthon Cioffi, DT Darius Hamilton, DE Julian Pinnix-Odrick

Reason for optimism: Janarion Grant is back after suffering an early injury that impacted Rutgers' offense. He is a dynamic playmaker, and adding him back into the mix, as well as some of the incoming freshman receivers, should help bring some positive production to the offense.

Cause for concern: There still aren't a lot of big playmakers on this team, on offense or defense. Head coach Chris Ash is doing a good job of recruiting the guys he wants, but they likely won't be ready to make a big enough impact this season.

X factor: Grad transfer quarterback Kyle Bolin recently was named the starter. If Bolin can give the offense a boost and provide some consistency, that will provide much-needed help at a position that has had a lot of uncertainty.

Game to watch: Sept. 1 vs. Washington

-- Tom VanHaaren

WISCONSIN BADGERS

Last year’s record: 11-3 (7-2)

Key returning players: LB T.J. Edwards, DB D'Cota Dixon, RB Bradrick Shaw, WR Jazz Peavy, TE Troy Fumagalli, C Michael Deiter

Key losses: OL Ryan Ramczyk, LB T.J. Watt, S Leo Musso, RB Corey Clement, RB Dare Ogunbowale

Reason for optimism: The Badgers maintain all the strengths that helped them win 11 games in 2016 to take on a far more manageable slate this fall. Instead of LSU, Ohio State and Michigan in the first half of the season, Wisconsin draws the likes of Florida Atlantic, BYU and Nebraska. Paul Chryst's team should once again be the favorite in the West, and it has as good a shot as anyone in the Big Ten to finish the season without a loss.

Cause for concern: If Wisconsin wants to take the leap from 10-win team to playoff participant, developing a more dangerous passing game would be a big help. Jazz Peavy is an exciting player, but he's the only returning receiver who made it to the end zone last season. Alex Hornibrook might need a few more options to keep defenses from neutralizing Peavy.

X factor: Or perhaps the extra option Wisconsin needs in the passing game will come solely from All-America-caliber tight end Troy Fumagalli. The 6-foot-6 senior gives Hornibrook a huge target in the middle of the field and showed his athletic ability while racking up 47 catches for 580 yards a year ago. If Chryst & Co. can find creative ways to get the ball into Fumagalli's hands, Wisconsin might have all the aerial firepower it needs.

Game to watch: Nov. 18 vs. Michigan

-- Dan Murphy