PHILADELPHIA — Time isn’t up for the biggest underdog of the N.C.A.A. men’s tournament just yet.

Tiny St. Peter’s University is alive and well and moving on to the final eight of the N.C.A.A. tournament after slaying yet another basketball powerhouse. Playing inspired defense and without any fear, the No. 15 seed Peacocks stunned No. 3 Purdue, 67-64, on Friday night before a crowd that included many St. Peter’s fans who made the trip down the New Jersey Turnpike and roared in approval.

The Peacocks (22-11) will advance to face the winner between No. 4 seed U.C.L.A. and No. 8 seed North Carolina in Sunday’s East regional final, with a chance to reach the Final Four in New Orleans. They have now knocked off No. 2 Kentucky, No. 3 Purdue and No. 7 Murray State to become the first seed 13 or lower to reach the final eight.

“I got a bunch of guys that just play basketball and have fun. That’s all we do,” St. Peter’s Coach Shaheen Holloway said in a television interview as his players drowned him out with jubilant celebrations.

The Peacocks captured national attention immediately after knocking off Kentucky — one of the national title favorites — before becoming just the third No. 15 seed to advance to the round of 16. St. Peter’s is the first New Jersey school to make it this far in the men’s tournament since Holloway was a point guard on the 2000 Seton Hall team.

The game was tight throughout with 15 lead changes, and both teams trading control deep into the second half. Purdue, known for its big, tall, athletic players, outrebounded and outscored St. Peter’s inside, but the Peacocks found a way to win anyway.

Matthew Lee tied the game at 57 with 3:17 remaining, and exactly one minute later Daryl Banks III hit a driving layup for the lead. The teams traded baskets and free throws, but Purdue was unable to catch up.

The Peacocks arrived for Friday’s game wearing T-shirts that read “More is Possible.”

“What are they going to say now?” Holloway said as his players celebrated. “See you later.”

Kansas is the only No. 1 seed to reach the round of 8.

CHICAGO — Kansas’ veteran lineup pushed into the round of 8 on Friday with a 66-61 win over Providence in a Midwest regional semifinal, becoming the only top seed to advance in a week when upsets have been the norm.

The Jayhawks controlled the matchup early on, blocking six Providence shots in the first 12 minutes and dominating the first-half rebounding game. But Providence, making its first Sweet 16 appearance in a quarter-century, punched back and kept the game within reach.

After trailing by as many as 13, Noah Horchler sunk two 3-pointers in quick succession to pull the Friars to within a point in the second half. Minutes later, he drove to the basket to give Providence a fleeting taste of the lead.

But it proved insufficient against an experienced Kansas team that was effective, even if sometimes inelegant.

Toward the end of the first half, Jalen Wilson, a Jayhawk forward, missed two layups, but got his own rebound each time and was able to coerce the ball through the hoop. Ochai Agbaji, a national player of the year finalist, made just 2 of 8 field goals. But with Kansas looking strained, and the Friars becoming more aggressive, Agbaji re-emerged late in the second half when Christian Braun served up an alley-oop from behind the 3-point line. Agbaji slammed it home, enlivening the Jayhawk fans at Chicago’s United Center who had been quiet for much of the night.

Kansas, whose youngest starter is a redshirt sophomore, was also able to lean on Remy Martin, a super-senior and Arizona State transfer, who led the Jayhawks in scoring with 23 points. Braun, a junior, and Wilson, a redshirt sophomore, both reached double digits in rebounds.

The Jayhawks will enter Sunday as a heavy favorite against either Iowa State or Miami, who were set to play each other later Friday. Iowa State is seeded 11th in the Midwest region, and Miami 10th.

But the Jayhawks’ performance on Friday, which followed a closer-than-hoped-for win against Creighton in the round of 32, did little to assuage concerns about their durability late in the tournament. Kansas is advancing to the round of 8 for the eighth time during Coach Bill Self’s tenure in Lawrence. Only one of those trips has ended with a national title.