MADISON, Wis. (AP) Wisconsin's defense is getting so picky.
The sixth-ranked Badgers have 11 interceptions over the last three games and 21 on the season, tops in major college football.
And now they are focused on Trace McSorley and No. 8 Penn State in the Big Ten title game on Saturday night.
''They've done a good job of playing the ball and ... looking for it,'' Wisconsin coach Paul Chryst said about his defense. ''Not just knocking it down, but let's get the pick.''
All those interceptions are, in part, a byproduct of the stout play of the front seven at Wisconsin (10-2, No. 6 CFP).
The defensive line has controlled the line of scrimmage, helping to free up a strong linebacker corps to make plays, whether in the backfield or in coverage. A secondary that had question marks at the beginning of the season has become a ball-hawking strength.
Safety Leo Musso, a former high school running back, has the speed to catch up to deep throws. He also has been displaying smarts in coverage, like when he stepped in front of a pass in the end zone last week against Minnesota after appearing to bait Mitch Leidner into making a seemingly safe throw.
''Our names are getting called but it's really the front seven doing their job,'' said Musso, who has four interceptions over the last three weeks. ''We have the easy job of just covering guys and catching the ball.''
But the quality of Wisconsin's competition hits a higher level Saturday when compared to the past three weeks. The Badgers had four interceptions apiece against Illinois and Minnesota, sandwiched around a three-pick game at Purdue.
Penn State (10-2, No. 7 CFP) presents a big-play problem.
McSorley has thrown just five interceptions all season. The Nittany Lions have 106 plays this season of 20 yards or more, with 57 coming through the air.
''I think the explosive plays come from Trace's mobility, when he is able to step up in the pocket and extend plays,'' Penn State coach James Franklin said this week. ''If you can buy time and extend plays and force people to cover longer than is normal, it's really challenging. So I think that's where a lot of our big plays have come from.''
Blitzing could be costly for the Badgers. McSorley was 12 of 15 for 245 yards and threw three TDs against the blitz in last week's 45-12 win over Michigan State .
Wisconsin has done a good job this year getting pressure with four rushers. Coordinator Justin Wilcox also has disguised rushes and blitzes, like he did last week against the Golden Gophers while rattling Leidner into a four-interception second half.
''Anytime you create some pressure on a quarterback, maybe the accuracy is off just a little bit, or the timing is off a little bit,'' Chryst said. ''You're thankful -those are big plays.''
Wisconsin has allowed just 40 plays of 20 or more yards, including 31 through the air and two touchdown passes. Cornerback Sojourn Shelton, a four-year starter, had two interceptions last week against Minnesota.
He is looking forward to what could be a track meet in the secondary with the Nittany Lions.
''It's going to be fun to play against these guys. This secondary group, we're all competitors. We all like to be put in challenging situations,'' Shelton said. ''So far we've excelled.''
AP freelance writers Dennis Semrau in Madison and Travis Johnson in State College, Pennsylvania, contributed to this report.
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