On Saturday, two teams will book spots in the Final Four of the men’s N.C.A.A. basketball tournament in New Orleans, while two others will see their seasons come to end.

The South and West regional finals will take place in San Antonio and San Francisco, while the East and Midwest finals will take center stage on Sunday.

Here’s what to watch for on Saturday.

All times are Eastern.

Villanova tries to make more history.

It’s March, so that must mean Coach Jay Wright and the No. 2-seeded Wildcats (29-7) are heating up at the right time. Villanova has won eight straight games dating to a Feb. 22 loss at Connecticut. The run has featured three victories in the Big East tournament at Madison Square Garden, and three during the N.C.A.A. tournament, including a 63-55 win over Michigan on Thursday in San Antonio.

Next up is a date with the No. 5 seed Houston (32-5), which has won six straight, is a 2-point favorite and ranks among the top 10 in both offensive and defensive efficiency (6:09 p.m., TBS).

“I think we’re beyond building,” Wright said after the win over Michigan. “We’re going to rest. We’re beat up. We’ve got to rest up. We can learn a little bit watching film. It’s about surviving now.”

Villanova is 19-3 in its last six N.C.A.A. tournaments and won the championship in 2016 and 2018. Those were the last two years in which the Final Four was broadcast on TBS instead of CBS. This year’s Final Four? Back on TBS again.

Houston wants a return ticket.

One year after leading the Cougars to the Final Four, Houston Coach Kelvin Sampson has his team within one victory of returning. And he has gotten here despite having five new starters.

All five of last year’s starters either moved on or suffered injuries. Quentin Grimes, a key player on last year’s team, is now on the Knicks’ roster. Guard Marcus Sasser, who scored 20 points as a sophomore in the national semifinal against Baylor a year ago, went down with a season-ending injury in December, as did the sophomore guard Tramon Mark.

Still, Houston has maintained its trademark defensive intensity, and it often seems as if the team has seven defenders on the floor, instead of five. In the second round, the Cougars limited Illinois to 34 percent shooting. Against No. 1-seeded Arizona on Thursday, they held the Wildcats to 33 percent while knocking off a single-digit seed for the first time since the 1984 Final Four, when Hakeem Olajuwon was a star.

“They’re not afraid of anybody, whether that’s U.A.B. or Illinois, Arizona, our next game Villanova,” Sampson said. “We’ll just move on to that one and we’ll do the best we can with that one.”

Coach K vies for a sixth title before retirement.

Duke, seeded No. 2, faced a real scare before eventually prevailing over third-seeded Texas Tech, 78-73, on Thursday night in San Francisco. The Blue Devils outscored the Red Raiders 12-5 in the last four minutes to give coach Mike Krzyzewski his 100th N.C.A.A. tournament win. Only five have more tournament wins than Krzyzewski’s 100 — Kentucky (129), North Carolina (128), Duke (117), Kansas (111) and U.C.L.A. (108).

The Blue Devils enter as 4-point favorites, but in order for Krzyzewski to reach his 13th Final Four — and first since the Blue Devils won their fifth championship in 2015 — they will have to handle Arkansas’s defensive pressure (8:49 p.m., TBS). In taking out Gonzaga, 74-68, on Thursday, the Razorbacks were relentless on the defensive end.

Duke’s sophomore point guard Jeremy Roach, who had 15 points, 5 assists and 4 turnovers against Texas Tech, will need another steady — and heady — performance.

“Just trust in your work,” he said. “These guys trust me, and the coaching staff trusts me.”

Arkansas looks to spoil Duke’s run.

Led by the former N.B.A. head coach Eric Musselman, the No. 4 Razorbacks (28-8) are in the round of 8 for the second straight season and are seeking to reach their first Final Four since 1995, when they were runners-up to U.C.L.A.

Playing aggressive defense, cutting off angles and stopping long outlet passes, the Hogs stunned Gonzaga, the tournament’s top overall seed. With both Gonzaga and Arizona going down on Thursday, it was the fourth time since the tournament expanded in 1979 that three No. 1 seeds lost before the round of eight; Baylor was ousted last weekend by North Carolina.

The senior guard JD Notae, who went for 21 points, 6 rebounds, 6 assists, 3 steals and 2 blocks against the Bulldogs, isn’t satisfied with stopping now.

“This is what we dreamed about,” he said. “This is what we came here to do. Coach said before we left Fayetteville, if we didn’t want to win, then don’t get on the plane. I feel like we brought that the whole time we’re here.”