SOUTH BEND — Brian Kelly looked around at a packed stadium and saw — fittingly enough — a sea of kelly green shirts.

On a day of firsts for Notre Dame’s new head coach, highlighted by a 23-12 win over Purdue, the colorful and enthusiastic crowd stood out. They were actually rooting for his team.

“Maybe this is just my background, but anytime I’ve gone into a stadium with 81,000, I’ve always played up to that opponent. Now, it was 81,000, and it was our people,” Kelly said. “The crowd was into it, and it was a great advantage.”

If the atmosphere was neat and the victory satisfying, the momento Kelly got after the game from athletic director Jack Swarbrick — the man who picked him for the job — was one for the trophy case.

Kelly got the game ball.

“That will be something that is very memorable,” said Kelly, who transformed programs at Grand Valley State, Central Michigan and Cincinnati into steady winners and now has his dream job. “Hopefully there are many more of those to come.”

Kelly has been heralded as a savior for a proud program that went 16-21 over the previous three years, and the team he took over last December showed promise in running his spread offense Saturday.

The Irish also played solid defense that was lacking last season. They had four sacks and two interceptions against Purdue’s Robert Marve.

“I took on the challenge at Noter Dame because I want to see this program back to where I believe it should be, and that’s amongst the elite in college football,” Kelly said.

“We’ve got some work to do. We are not there yet, believe me. Trust me. But we took a step today, and we’re going to keep pounding at it and working at it.”

Quarterback Dayne Crist passed for 205 yards and a touchdown in his first start, while running back Armando Allen had a 22-yard TD run in the first quarter and set up another with a punt return.

Of course, most Notre Dame coaches win their first game. Kelly’s victory gives Notre Dame coaches a 26-3 record in their debuts, dating back to 1896. The only three to lose in their first games coaching the Irish were Frank E. Hering in 1896 (4-0 loss to Chicago Physicians and Surgeons), Elmer Layden in 1934 (a 7-6 setback to Texas) and Lou Holtz in 1986 (a 24-23 defeat at the hands of Michigan).

Notre Dame led 20-3 after three quarters before Purdue rallied behind the Miami, Fla., transfer Marve, who got the Boilermakers back in the game with a 23-yard TD run early in the final period but was penalized for celebrating.

David Ruffer kicked three field goals for the Irish, including a 37-yarder with 4:30 left to restore the lead to 11.

Marve’s 23-yard TD run on a fourth-and-1 with 11:55 left got the Boilermakers back in the game at 20-12. But he dived into the end zone after he crossed the goal line, resulting in an unsportsmanlike penalty for celebrating and hurting Purdue’s field position the rest of the game.

“I think I got a little bit too excited,” Marve said.

Purdue had to kick off from the 15 after the penalty on Marve and Notre Dame Cierre Wood made a nice 38-return to the Boilermakers 41 before fumbling with Irish teammate Zeke Motta pouncing on the ball.

But the Boilermakers dug in and forced a punt, taking over at their own 12 with 9:47 remaining. They were set back by a pair of penalties and after a long pass to Justin Siller fell incomplete, the Boilermakers punted out of their own end zone.

Notre Dame then moved in for Ruffer’s third field goal and regained control.

Marve completed 31 of 42 passes for 220 yards. Crist was 19 of 26, solid but far from spectacular running Kelly’s fast-paced spread offense. Purdue’s talented wideout Keith Smith made 12 catches for 80 yards.

“The second half, I felt like I was rolling,” Marve said. “I thought personnel, we matched up pretty well against them, I felt comfortable in our scheme. I felt that we had a chance to win. Even with that, I felt there were some plays we needed to make, and we didn’t come up with it today.”

On the first play of the final quarter, with Notre Dame ahead 20-3, Marve’s fourth-and-1 pass from the Notre Dame 5 was tipped and intercepted by nose guard Ian Williams. But Purdue star defensive end Ryan Kerrigan and Charlton Williams then dropped Allen in the end zone for a safety.

After the free kick, the Boilermakers drove in for the score with Marve using a nice fake to break free on his 23-yard run.

Crist’s 5-yard TD pass to freshman TJ Jones early in the third came just a little over two minutes after Allen picked his way on a 38-yard punt return to the Purdue 30. The score put the Irish up 20-3.

After Crist hooked up with Floyd on a 34-yard pass, he hit the usually sure-handed Floyd again as he slanted toward the end zone and the Irish seemed poised to build on their 17-point lead. But Floyd was hit by Will Lucas at the 2, fumbled and Logan Link recovered for Purdue to cut off another Irish scoring threat.