Dallas ? With the game tied late in the second half and their leading scorer in foul trouble, Oklahoma State needed someone to make a big play.

Good thing they had two conference players of the year around.

Tony Allen, the coaches’ pick for the Big 12 Conference’s top player, made a key steal and John Lucas, the media’s choice for the same honor, followed with a short jumper and a wide-open three pointer, sending the No. 7 Cowboys past Iowa State, 83-75, in the second round of the Big 12 tournament.

“That’s the thing that’s impressed me with this team all year long — they keep their poise, don’t panic and they all have big ol’ hearts,” Oklahoma State coach Eddie Sutton said. “They always feel like someone is going to step up.”

Joey Graham, who made 11-of-13 shots for 25 points, carried the top-seeded Cowboys (25-3) until picking up his fourth foul with 8:00 left. The Cyclones (17-12) tied it at 59 soon after.

Then came Allen’s steal off an inbounds pass. He dribbled down and found Lucas on the baseline for the go-ahead bucket. After Jackson Vroman missed two chances for Iowa State to tie it, he dove to steal the ball from Lucas and gave the point guard a clear look at the basket.

Oklahoma State followed with two free throws from Graham, two nifty layups in traffic by Ivan McFarlin and a pull-up jumper by Lucas, capping a 13-4 run that put the Cowboys ahead for good.

Although Iowa State never got closer than five again, it wasn’t easy for Oklahoma State because Allen and McFarlin also were playing with four fouls.

Graham, who also had nine rebounds, tied a tournament record for field-goal percentage at .846.

Oklahoma State's John Lucas grins as the game ends against Iowa State. The Cowboys beat the Cyclones, 83-75, Friday in Dallas in the quarterfinals of the Big 12 Conference tournament.

Lucas scored 23 points and Allen added 14 points, seven assists, five rebounds and three steals. McFarlin scored 12 as the Cowboys advanced to a semifinal today against Texas Tech.

“It’s not like we have only one guy who can go out and do it, we have three or four,” Lucas said. “If defenses focus on one person, we have other options.”

Oklahoma State ended a three-game losing streak at the conference tournament, giving Sutton a nice 68th birthday present. Fans celebrated by serenading him with “Happy Birthday” after the final buzzer.

“My birthday always falls during tournament time, so you never really get to celebrate,” Sutton said. “But at my age, you don’t want to celebrate.”

The Cyclones were hoping to avenge their only home loss, a 21-point rout in February. They failed to score a basket the final 3:11 of the first half and were down 12 early in the second before tight defense and sloppy play by Oklahoma State turned it into a game again.

A thunderous dunk by Marcus Jefferson off a perfect floating alley-oop pass from Will Blalock tied it with 7:44 left. Jake Sullivan kept Iowa State within 64-62 by hitting a three-pointer — the only one he made in six tries — but the Cyclones ran out of answers.

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“They played as hard as they could and tried as hard as they could,” coach Wayne Morgan said. “That’s all you can ask for.”

Vroman led ISU with 24 points before fouling out with 1:09 left. He also had 10 rebounds. Sullivan scored 19, and Jared Homan had 13 points and 13 rebounds.

“It was a pretty evenly played game then Lucas hit two big shots,” Sullivan said. “Then they got a couple of breaks and ended up winning the game.”