MADISON, Wis. -- After watching a comfortable fourth-quarter lead melt away in a matter of minutes, No. 12 Wisconsin needed a big defensive play from Ethan Hemer to fend off FCS school Northern Iowa on Saturday.
The redshirt junior defensive lineman batted down a pass by Panthers quarterback Sawyer Kollmorgen on fourth-and-1 in Wisconsin territory, allowing the Badgers to escape with a 26-21 victory over the Panthers -- who showed why they're regarded as one of the top teams in Division I's second tier.
Badgers coach Bret Bielema figured his team might learn more from a close call than a big blowout to start the season.
"You've got to touch a hot stove once," Bielema said. "Once you get burned, you're not going to do it again. And hopefully our guys learn, hey, you've got to put people away when we can."
Montee Ball rushed for 120 yards and a touchdown for the Badgers, while new starting quarterback Danny O'Brien completed 19 of 23 passes for 219 yards and a pair of touchdowns to Jared Abbrederis in his debut.
"I believe we didn't make the statement that we wanted to," Ball said. "But I believe this was a great learning experience for us all, because we believe that the mentality (we had) toward the game, we weren't attacking the defense like we should have. But it's a lot easier to correct your mistakes after a win than a loss."
Kollmorgen threw for 265 yards and three touchdowns.
It was another huge effort against superior competition for the Panthers, who had one-point losses at Iowa in 2009 and at Iowa State last season. Northern Iowa beat Iowa State in 2007.
"Without the batted ball, we might still be playing," Northern Iowa coach Mark Farley said. "A guy got a hand up, so credit him."
Kollmorgen said the Panthers didn't get what they wanted, but should leave with their heads held high.
"Coach Farley said to come out and prove we belong," Kollmorgen said. "We did that today."
Despite their classification, Bielema said he knew the Panthers would put up a fight.
"There's a lot of FBS schools that I'd rather play than those guys," Bielema said. "They're a really, really good football team."
Although the Badgers got off to a sluggish start on offense, they appeared to be on track for a fairly comfortable win.
Wisconsin's defense didn't allow Northern Iowa on its side of the 50-yard line until the 4:27 mark in the third quarter -- but then the Badgers nearly melted down.
Leading 26-7 in the fourth quarter, Wisconsin allowed Kollmorgen to throw a pair of long touchdowns to David Johnson, cutting the lead to five.
After forcing a Wisconsin punt, the Panthers drove again.
Facing fourth-and-1 at the Wisconsin 41-yard line, Hemer tipped the ball at the line of scrimmage to stop the drive.
"To me, we get a lot better out of this than a 42-0 blowout," Bielema said. "I don't see what that gets. I know our fans, it kept them in their seats."
The Badgers won their 15 consecutive season opener, extended their home winning streak to 17 games, the second-longest streak in school history, and have now won 33 consecutive regular-season nonconference games.
It was an efficient day for O'Brien, a transfer who was eligible to play for the Badgers right away because he already had graduated from Maryland -- the same rule Russell Wilson took advantage of to play for the Badgers last year.
Coaches and teammates went out of their way this week to establish realistic expectations for O'Brien and shield him against direct comparisons to Wilson -- a remarkable playmaker who led the Badgers to a Big Ten title and Rose Bowl appearance last season, and now has won a starting job with the NFL's Seattle Seahawks as a rookie.
"We weren't consistent on our side of the ball, but you take a win any way you can get it," O'Brien said. "(The score was) too tight, whatever you want to say. You want to win easily, obviously, but you take a win any way you can get it."
For Ball, it was a chance to brush off his recent off-the-field trouble. Ball was beaten up in an attack near campus a month ago, sustaining a concussion and missing part of camp.
"I know, and everyone else should know, that I'm going to come back even stronger next game and it will take off from there," Ball said.
It also was the debut for Badgers offensive coordinator Matt Canada, who replaced new Pittsburgh head coach Paul Chryst.
Bielema, who has grown fond of saying there might be sexier teams in college football than Wisconsin, stuck with that theme in summing up Saturday's win.
"Wisconsin football may not be the prettiest thing to watch, but we get Ws," Bielema said.
Running back Devontae Booker had 124 combined yards and a touchdown, and Utah spoiled Jim Harbaugh's Michigan coaching debut, beating the Wolverines 24-17 on Thursday night.
Arizona star linebacker Scooby Wright will have an MRI after injuring his left knee in the first quarter of the Wildcats' season-opening 42-32 win over UTSA on Thursday night.
Trevone Boykin threw for 246 yards and a touchdown and ran for 92 yards and another score to help No. 2 TCU outlast Minnesota 23-17 on Thursday night.
All-American defensive end Shawn Oakman and safety Orion Stewart have been suspended for Baylor's season opener Friday against SMU for a violation of team rules, a school spokesman told ESPN.com.
Ohio State quarterback Cardale Jones is "doing fine" after he was released from the hospital Wednesday night after being treated for symptoms related to a migraine headache.
East Carolina receiver Trevon Brown will miss three games after being placed on probation for a violation of the school's student code of conduct.