Tom Dienhart, BTN.com Senior Writer, September 16, 2012

A week after suffering through the conference's first six-loss non-conference week since 2000, the Big Ten bounced back with an 10-2 clip in Week 3 action. The victories included wins over BCS foes Cal and Boston College, one week after the Big Ten went 1-6 versus such foes. Northwestern, for the third consecutive week, notched a win over a BCS team.

What did I learn from Week 3 action? See the five biggest things in this post.

1. The Legends Division race just got a whole lot more interesting with Michigan State?s 20-3 loss to Notre Dame. And wins by Nebraska and Iowa pumped some life into those programs, while Michigan keeps moving forward. Meanwhile, Northwestern and Minnesota are the lone unbeatens in the division. This is gonna be fun, people.

[Related: Who lands where on Dienhart's Week 4 Power Rankings?]

2. Michigan State may have some big concerns on offense. The Spartan defense played well enough to beat Notre Dame on Saturday night, allowing just 300 yards. But the Spartan attack needs to amp up the passing game coming off the program?s worst offensive showing (237 yards) at home since a 20-3 loss to Central Michigan in 1991. Le?Veon Bell is a top-flight running back who had 77 yards on the ground, but MSU can?t ride him to victory over quality foes. Quarterback Andrew Maxwell and the passing game need to develop. He hit 23-of-45 passes for 187 yards vs. ND. But an even bigger issue may be an offensive line that time and again allowed the Fighting Irish to pressure Maxwell and yielded four sacks after MSU had permitted no sacks the first two games.

[Related: Dienhart: Spartans' loss leaves that sinking feeling]

3. Purdue?s offense may have big-play ability after lacking it in 2011. At least it showed some on Saturday vs. an overmatch Eastern Michigan squad. The Boilermakers scored on a 40-yard run, 50-yard run, 87-yard run and 56-yard run en route to rushing for 392 yards. With QB Robert Marve hurt, the Boilermakers will need to find ways to score quickly and not have to rely on 10-, 11-, 12-play drives to score. This just may be a sleeper team in the Leaders Division.

4. The Nebraska defense is back-at least for a week. Last week in the Rose Bowl vs. UCLA, the Husker defense allowed 653 yards-the second most ever in school history–in a 36-30 loss. On Saturday vs. Arkansas State from the Sun Belt, the Cornhuskers defense allowed just 286 yards. Nebraska sat on Arkansas State?s passing attack, yielding just 138 yards on 16-of-32 passing. That?s only 4.3 yards per pass. Nebraska mixed up personnel and came out in a 3-4 look instead of their usual 4-3 scheme. This is exactly what Nebraska?s defense needed after that dark say in SoCal.

[Related: Read Dienhart's Snap Reactions from Week 3]

5. The Big Ten has nice depth at quarterback. We?ve already seen signal-callers at Illinois (Nathan Scheelhaase), Indiana (Tre Roberson), Purdue (Robert Marve) and Minnesota (MarQueis Gray) go down with injury. And each time, another player has stepped in and done well. In fact, multiple quarterbacks at other schools also have seen action and had degrees of success, including Cameron Coffman and Nathan Sudfeld at Indiana; Kain Colter and Trevor Siemian at Northwestern; Danny O?Brien and Joel Stave at Wisconsin. Steven Bench also has played at Penn State, while Rob Henry is part of the action at Purdue.

BTN.com senior writer Tom Dienhart is a veteran sports journalist who covers Big Ten football and men's basketball for BTN.com and BTN TV. Find him on Twitter and Facebook, read all of his work at btn.com/tomdienhart, and subscribe to his posts via RSS. Also, send questions to his weekly mailbag using the form below and read all of his previous answers in his reader mailbag section.

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