ST. LOUIS -- Wisconsin found just enough offense in the nick of time.

Vitto Brown's 3-pointer with 2:34 left gave the Badgers the lead for good as they held off Pittsburgh 47-43 Friday in a first-round matchup of the NCAA Tournament's East Region at Scottrade Center.

Both teams are 21-12, but it is seventh-seeded Wisconsin that moves on to a matchup Sunday with either second-seeded Xavier or 15th-seeded Weber State.

"I'm not sure what we shot," Wisconsin guard Zak Showalter said, "but it was ugly. I saw someone tweet that it was classic Wisconsin basketball. We just had to grind it out."

Wisconsin's Ethan Happ, who led all scorers with 15 points, added a bucket in the lane while being fouled at the 1:43 mark to make it 44-40. Panthers forward Jamel Artis canned a 3-pointer with 40.6 seconds remaining to cut the lead to a point.

Pittsburgh had a chance to take the lead, but guard James Robinson missed a driving layup in heavy traffic after being bumped by teammate Michael Young.

Robinson went the length of the court after grabbing the rebound of a missed 3-pointer by Nigel Hayes. As Robinson stutter-stepped just outside the lane, he stumbled for an instant after clipping Young and couldn't quite gather himself to make the strongest possible move.

"It just happened," Robinson said. "He didn't intend to bump me and I didn't intend to run into him. I'm just trying to get the best shot I can."

Happ was fouled on the rebounding action with 2.0 seconds remaining and made one of two foul shots, with Hayes grabbing the miss of the second free throw. He was fouled and drilled both his foul shots to seal the verdict.

Hayes added 12 points despite hitting only 3 of 17 field-goal attempts and Brown finished with 11.

Artis was the Panthers' only double-figure scorer with 13 points.

Pittsburgh took a quick lead as Robinson attacked slower defenders for six points in the game's first six minutes, giving the Panthers a 10-3 lead at the first TV timeout.

The first half's other storyline was Wisconsin's futility offensively. The Badgers started the first half 2-for-14 and fell behind 18-6 on a jumper by guard Chris Jones at the 7:04 mark.

But the Panthers couldn't put Wisconsin away, managing just two buckets on their final 10 possessions of the half. The Badgers managed to make a bit of headway, cutting their halftime deficit to 22-16 on a 3-pointer by Brown in the final minute.

The teams combined to hit just 16-of-51 field- goal attempts before halftime. In an interesting twist, Pittsburgh also led the rebounding battle 22-16.

However, the Panthers ran into instant trouble early in the second half as they couldn't defend without fouling. They were whistled for four fouls in the first 98 seconds and put Wisconsin in the bonus less than five minutes into the half.

Pittsburgh coach Jamie Dixon, who frequently expressed his displeasure with the officials as the fouls piled up, admitted his team could have done a better job of playing through its foul issues.

"It was a drastic change, but we came up short," he said. "Our goal was to get to the foul line more than our opponent and we weren't able to do that. I'm proud of our effort, but it came down to not making enough shots or getting to the line."

The Panthers, who entered the night averaging more than 21 foul shots per game, attempted only seven, making four.

Ultimately, the game was a microcosm of the Badgers' season: a slow start, followed by gradual improvement and then the result when it mattered.

"It speaks volumes to our own resilience," guard Bronson Koenig said. "At this time of the year, you'd rather have an ugly win than a pretty loss."

NOTES: Pittsburgh G James Robinson is the fifth player in program history to record at least 1,000 points, 500 assists, 350 rebounds and 150 steals in his career. ... Wisconsin's average of 21.7 free throw attempts per game led the Big Ten this season. ... The Badgers' 18 straight trips to the NCAA Tournament is the fifth-longest streak in event history.