Iowa St. downs No. 13 Oklahoma St.

AMES, Iowa (AP) — Iowa State put its NCAA tournament hopes in jeopardy with a contentious home loss to Kansas and a brutal defeat at Oklahoma.

The Cyclones should feel much better about their postseason chances after holding off No. 13 Oklahoma State.

Senior Will Clyburn scored 20 points and Iowa State beat the Cowboys 87-76 on Wednesday night to bolster its NCAA tournament hopes.

Georges Niang added 18 points for the Cyclones (20-10, 10-7 Big 12), who notched just their second victory over a ranked opponent this season.

"That definitely hit us," Iowa State's Chris Babb said about the Cyclones losing 108-96 in overtime to the Jayhawks and 86-66 to the Sooners last week. "We came too far. We've worked too hard to let this team that we built ... just kind of wither away. And it was going in that direction."

It almost went that way against the Cowboys.

This time, Iowa State got stops when it needed them.

Oklahoma State trailed by as many as 15 points, but Marcus Smart's reverse dunk made it 70-68 with 4:28 left. Clyburn answered with a 3 and Tyrus McGee's 3 a minute later put the Cyclones ahead 78-68.

Smart was brilliant for Oklahoma State (22-7, 12-5), scoring 24 points with eight rebounds and five steals. But it wasn't enough as the Cowboys lost for just the second time in 12 games.

"They deserved it. We knew they were going to come out like kind of a caged lion," Oklahoma State coach Travis Ford said. "They came up with big plays when we kept trying to cut (the lead)."

Oklahoma State's last three wins were by an average of double digits and the Cowboys were rolling ahead of a key final league week against the Cyclones and No. 9 Kansas State.

There were only glimpses on Wednesday of the team that's spent the last six weeks plowing through the Big 12.

The Cowboys got within 67-64 after two steals by Smart led to two baskets. Smart made it a two-point game with his reverse in transition, but Clyburn's huge response gave the Cyclones the school record for 3s in a season.

"Will was terrific. He was very aggressive all game long," Iowa State coach Fred Hoiberg said. "I heard a guy behind me yell 'Why?' and then it went it."

Le'Bryan Nash and Markel Brown both had 14 points for the Cowboys, who shot an abysmal 4 of 23 from 3-point range.

"We got back in the game a couple of times, but we never could quite get over the hump," Ford said. "I think that probably got them in the (NCAA) tournament. I thought they were already in."

Oklahoma State was one of four teams to rally from behind and beat Iowa State in the final minute this season.

The Cyclones did their best to ensure they wouldn't be in such a position again.

Iowa State, which blew a lead in the final minute and lost on Smart's buzzer-beater on Jan. 30, started the game on a 30-15 run. Niang buoyed the early spurt with 12 points, and Iowa State held the Cowboys scoreless on nine tries from 3-point range in building a 10-point halftime lead.

Niang swatted away an alley-oop pass before it got anywhere near the rim to open the second half. Clyburn followed with a transition 3, and Iowa State was off and running again.

McGee finished with 14 points and Melvin Ejim had 13 points and 12 rebounds for the Cyclones.

"I think the difference between most late-game situations, we just continued to be aggressive down the stretch," Babb said.

The Cyclones, who are 16-1 at home, finish the regular season on the road against West Virginia on Saturday. Though Iowa State is in much better shape for the postseason after beating the Cowboys, it might need to beat the Mountaineers to ensure they don't have another home game this season — in the NIT.

The loss shouldn't impact Oklahoma State's postseason outlook all that much. The Cowboys faced an uphill climb in moving past Kansas and Kansas State in the Big 12 standings anyway, and they will get another chance at a marquee win against K-State on Saturday.

"Every game is a big game this time of year. Obviously Kansas State is having a heck of a year," Ford said.