After a 2020 season that allowed players to transfer with instant eligibility, sit out a season, and return for another, it's hard to keep track of who all will be playing this season in the Big Ten Conference. More importantly, who will be putting on the most impressive performances?

We begin our annual Ranking the Big Ten series today with the quarterbacks, a group of athletes looking to reestablish themselves, veterans, and an interesting newcomer.

Redshirt Junior Michael Penix Jr. led Indiana to a 6-2 overall finish in the 2020 season and was a wonder to watch while he battled the best in the Big Ten.

Against Ohio State, the reigning four-time defending Big Ten champs, Penix Jr. completed 27 of 51 for 491 passing yards, including a 68-yard bomb, in the Hoosiers' only regular-season loss. Indiana lost 42-35 after Penix Jr. led his troops to score 28 points in the second half.

According to Pro Football Focus's (PFF) grades, Penix Jr. played his best game of the entire season against Ohio State, the CFP runner-up.

The quarterback's completion percentage when down 13 percent from 2019 (69%) to 2020 (56%). Factors outside of the quarterback, like receivers, control a lot of this percentage. That said, he will still need to step up his game to give Indiana a fighting chance now that he has several reliable receivers like Ty Fryfogle.

The 2020 second-team All-Big Ten selection is prone to injury. A torn ACL shortened his season even more in 2020, and another injury did the same in 2019. If he can fully recover from an ACL injury and stay healthy, the Big Ten better watch out for this fearless quarterback.

The next quarterback in line to head one of college football's most dominant teams is redshirt freshman C.J. Stroud. With Justin Fields headed to the Chicago Bears, Stroud has big shoes to fill at a very young age. But who says he doesn't have the equipment to do so.

At Rancho Cucamonga (CA) High School, Stroud had 3,878 passing yards with a 66% completion rate during his senior season. He connected for 47 touchdowns through the air with nine interceptions in 12 games.

During his redshirt freshman year at Ohio State, Stroud had one rushing attempt against Michigan State on a designed quarterback keep. He rushed from 48 yards and a touchdown.

Stroud has minimal experience at the helm of a top Power Five Team. But with world-class coaches, teammates, and a first-round pick predecessor to learn from, expect Stroud to do big things this season.

Husker quarterback Adrian Martinez and his head coach Scott Frost are entering their fourth year together at Nebraska. The stakes are high, and Martinez is not shielding away from the pressure.

Last season, Martinez battled for the starting position against sophomore Luke McCaffrey, who has since left the program. QB1 is his once again, but he needs to play like it can be taken away at any moment. Nebraska is desperate for a winning season.

Despite the criticism, Martinez had his best season in 2020 in his offense grade (77.9) and run/rushing grade (80.8), according to PFF. His best passing season grade (71.1) was his freshman season. Martinez needs to get back to completing more passes. He has personnel he can rely on with deep wide receiver and tight end rooms.

Nebraska quarterback coach Mario Verduzco has been preaching that Martinez must reduce his turnovers. If he can do that and up his completion percentage, Martinez could lead Nebraska to success.

Minnesota quarterback Tanner Morgan had a rude awakening in 2020 when the Golden Gophers went 3-4 after an 11-2 finish in 2019. How Morgan bounces back for his senior season will determine the fate of P.J. Fleck's team.

In 2019, Morgan set 10 of Minnesota's season records, including passing yards (3,253), touchdown passes (30), completion percentage (66%), and touchdown-to-interception ratio (30-to-7). That was his best season, with an 85.5 offense grade on PFF and an 89.1 passing grade.

The 2020 All-Big Ten Honorable Mention needs to find a way back to his 2019 self. In 2020, Minnesota faced uncontrollable difficulties with COVID-19 and players opting out. A sense of normalcy and consistency might help Morgan lead his team to a winning season.

Like two other quarterbacks on this list, Penn State quarterback Sean Clifford is a three-year veteran in his team's offense and entering his third calling the plays. Penn State's current all-time leader in career passing efficiency rating (146.8), he holds the second all-time in completion percentage (.600).

After a heartbreaking loss to Indiana in overtime to start the 2020 season, Penn State lost four consecutive games. The Nittany Lions then rallied and beat its last four opponents.

The difference between the last four games was Clifford's performance. His top four PFF offense grades were against three teams PSU beat: Michigan (80.2), Indiana (78.9), Rutgers (72), and Michigan State (71.3). Penn State ended its season with momentum, which ideally carried into the offseason.

At his best during his sophomore season, Clifford led Penn State to an 11-2 finish and defeated Michigan 28-21 in an electric game. The Big Ten knows Clifford can dominate. The question is whether he can return to his best or even better?