Northwestern quarterback Dan Persa, left, is sacked by Penn State defender Devon Still (71) during the fourth quarter an NCAA college football game in State College, Pa., Saturday, Nov. 6, 2010. Penn State won 38-21. (AP Photo/Gene J. Puskar)

Perhaps no team in college football lives on the edge as much as the Northwestern Wildcats.

The Wildcats (6-3, 2-3 Big Ten) began their Big Ten schedule with a one-point win at Minnesota. Then, it was a three-point loss to Purdue in Evanston, a 35-27 come-from-behind defeat to Michigan State also at Evanston, a three-point win at Indiana and then last Saturday’s collapse at Penn State.

The thing about living on the edge is sometimes you fall off.

After building a 21-0 lead against Penn State, the Cats fell off. The rest of the game went 35-0 in favor of Penn State and coach Joe Paterno had his 400th win.

The Wildcats will host No. 13 Iowa (7-2, 4-1) this Saturday with questions to answer, if not for their constituency then for themselves.

“We kept on battling and we put a great drive together and just fell short there and that would have been key,” NU coach Pat Fitzgerald said after Penn State. “But I’m proud of our guys’ fight and now we get to go home and we have three rivalry games left and our guys will be excited.”

And there it is. There’s the attitude that explains Northwestern’s recent success against the Hawkeyes.

The Wildcats have reeled off two straight victories over Iowa, with both coming in Kinnick Stadium, including last season’s upset that took a huge chunk out of Iowa’s Big Ten title hopes. Northwestern has won four of five from the Hawkeyes because it pulls out all the stops in what it considers a rivalry game.

Northwestern quarterback Dan Persa was a backup quarterback going into the rivalry last season. Because of injury, Persa found himself leading the Wildcats to victory at Kinnick. He rushed for 67 yards and threw a TD in a victory that was Iowa’s first loss of ’09 and snapped Iowa’s 13-game winning streak.

His performance a year ago in Kinnick was prelude to a sparkling 2010. Persa, a 6-foot-1, 210-pounder, is second in the Big Ten in total offense 303.6 yards a game. He leads NU in rushing with 469 yards. He’s 25th in the country in a category called “points responsible for” at 14.00 points a game. By the way, Iowa quarterback Ricky Stanzi is No. 20 on this list with 14.67 points a game.

At Penn State last week, Persa accounted for 310 yards and three scores.

“Dan is a warrior,” Fitzgerald said. ”If you give me 22 Dan Persa’s, I’ll show you a Super Bowl and a National Champion. He’s a war-daddy and he gives everything he’s got on every single play and he’s a great leader. We wouldn’t be in the position we are at to have a significant month without him.”

The head coach has to call his quarterback “war daddy” when he’s been sacked 31 times this season, the most in the Big Ten and 114th out of the 120 FBS schools. He suffered a concussion against Indiana, but returned and produced at Penn State.

He was asked if he can stay in one piece.

“Yeah, I feel fine,” Persa said. “I agree, I need to do a better job of getting down.”

Persa is working for Northwestern. What isn’t working is the defense, specifically the pass defense.

Northwestern is 10th in the conference allowing 247.3 yards a game through the air. But that only tells part of the story. Northwestern has 11 interceptions this season, which is fourth in the Big Ten. A team that lives on the edge needs to win turnover battles, and the Cats have won more than they haven’t at plus-6, third in the Big Ten behind Ohio State (plus-13) and Iowa (plus-12).

But one emphasis for Fitzgerald, a former all-Big Ten linebacker for the Cats during a Rose Bowl run, was missed tackles.

Fitzgerald said Monday he counted 27 missed tackles against Penn State.

“It’s not real hard, it’s not real complicated. You play defense, you tackle people,” Fitzgerald said. “Your number gets called, you’re at the point of attack, you’ve got to tackle. . . You do that, guys go on the ground and you stop the run.”

Sounds as though the coach is in the mood for a rivalry game.

2010 Nu Iowa