What is Northwestern's Clayton Thorson working on in spring practice?

Northwestern had an up-and-down season in 2016, losing its first two games to Western Michigan and Illinois State but rebounding to make -- and win -- a bowl game.

The Wildcats dropped off the national radar in some respects after that tough start, which obscured a really big development. That is, the actual development of quarterback Clayton Thorson.

As a redshirt freshman starter, Thorson helped lead the team to 10 wins, but he wasn't asked to do much more than manage the game. As a sophomore, Thorson showed vast improvement in virtually all areas. He more than doubled his passing yards, to 3,182, while throwing 22 touchdowns and just nine interceptions. In Big Ten games, he completed 60.9 percent of his passes with a 17 touchdowns and just six intereceptions.

Thorson has quietly turned into one of the top quarterbacks in the league and one of the more promising young signal-callers in the country. Continuing in our series looking at the to-do list for the Big Ten's top individual returners and some of their key statistics, let's see what Thorson should be working on this spring:

1. Avoiding the rush: This is by no means all on him, but Thorson was sacked 38 times last year, which ranked 118th among FBS quarterbacks. He also fumbled five times while being sacked and completed just 33.6 percent of his throws versus pressure. Of course, the offensive line has to do a better job against the pass rush, and receivers and running backs have to pick up their blocks. Still, as Thorson matures, he should continue to get a better feel for where the pressure is coming from, find safety valves and throw the ball away rather than take a sack when possible.

2. Pick spots in the running game: As long as Justin Jackson is still around, Northwestern won't have to rely on Thorson running the ball. He turned into a very good pocket passer and deep-ball deliverer last year. Yet Thorson has good wheels and showed that off with some big runs as a redshirt freshman, when he had 397 rushing yards. That dipped to just 98 total rushing yards last season, a figure hurt by all of sacks. The Wildcats don't want him to get hurt while running, but the judicious use of scrambles could add an extra layer to the offense.

3. Develop chemistry with new receivers: Much of Thorson's growth was tied into the unexpected star turn by Austin Carr last season. The senior receiver came out of nowhere to become a Biletnikoff Award finalist with 90 catches for 1,247 yards and 12 touchdowns. Carr had an uncanny ability to get open despite defenses geared to stop him, and Thorson completed 68.2 percent of his targets to Carr. But with Carr and second-leading receiver Andrew Scanlan both graduated, that's 42.5 percent of Thorson's 2016 completions gone. This offseason is a key time for Thorson to develop chemistry with guys such as Flynn Nagel, Garrett Dickerson and Oregon transfer Jalen Brown, much like he did last spring and summer with Carr.