With the many great achievements that have come in Bruce Weber's first season as coach at Kansas State, he couldn't remain too downtrodden that his ninth-ranked Wildcats came up short in their regular-season finale.

Le'Bryan Nash scored 24 points, Marcus Smart added 21 and No. 13 Oklahoma State beat the Wildcats 76-70 on Saturday in a game with Big 12 championship implications.

The Wildcats (25-6, 14-4) came into the day tied with rival Kansas for the conference lead, but were left needing the Jayhawks to lose on the road at Baylor later Saturday to come away with their first regular-season conference title since 1977 in the Big Eight.

"We had an opportunity to be regular-season conference champs," senior Rodney McGruder said, "and we let that opportunity slip."

Kansas State still finished with the most regular-season wins in school history, and Weber has the most wins by any K-State coach in his debut season.

"It's been fun. It's been a blast," Weber said. "I just hope, for their sake, there's some more good things to come. ... We lost one game at a top 13 (team) in the country. It's not like it's a disaster, but it's disappointing."

K-State led by as much as nine in the second half and was up 61-57 following McGruder's three-point play with 4:45 remaining. Weber thought the game turned on the Wildcats' next possession.

After officials had stopped the game to review a Smart jump shot and rule that it was not a 3-pointer but a 2, he got between Angel Rodriguez and the sideline and drew an offensive foul as Rodriguez tried to catch an inbound pass.

The Wildcats missed their next eight shots as Oklahoma State (23-7, 13-5) went on a 14-1 run to claim the lead for good. Besides drawing the charge, Smart had six points during the run.

Smart said there had been some buildup to the call, with referees warning both Smart and Rodriguez to stop pushing off.

"At that moment in time, he gave me a little nudge that was enough for the referee to blow his whistle," Smart said. "Actually, I wasn't trying to fall. I actually slipped and it just looked like I fell, like I tried to make it a flop. But I actually slipped. It was a nudge but it wasn't enough to make me fall."

Weber wasn't sold on the call.

"I bet if you went and watched it, it wasn't an offensive foul. So, that changed the game, the momentum a lot," Weber said. "But then they made plays and we didn't."

Smart then got fouled by Thomas Gipson on a 3-point attempt and hit two free throws to tie it. Nash followed with a driving layup to put the Cowboys ahead to stay at 63-61 with 2:47 remaining. Oklahoma State hit 13 straight free throws during crunch time to seal it.

"The momentum changed for us, and we opened the game up," Smart said.

McGruder led the Wildcats with 22 points. He had a big game when the teams met in the Big 12 opener, scoring 28 points and making all five of his 3-point attempts to lead K-State to a victory. He couldn't match that this time, connecting on only six of his 15 shots.

Gipson chipped in 15 points and Rodriguez scored 10, but also struggled to a 3-for-16 outing.

"They've got some pretty good athletes that can guard and defend, and they made their focus — there's no doubt — to make sure that Rod and Angel were jammed up as much as possible," Weber said.

Markel Brown scored 16, including seven free throws in the final 2 minutes for Oklahoma State.

The Wildcats will be the No. 2 seed in next week's Big 12 tournament. Oklahoma State will be the third seed and face Baylor in the opening round.

The Wildcats allowed Oklahoma State to shoot 57 percent while making just 39 percent of their own shots, but still managed to hang in until the final minutes for a chance to stretch their winning streak to seven and — more importantly — win an elusive conference title.

Shane Southwell and Martavious Irving hit 3-pointers to get the Wildcats going after trailing 36-30 at halftime, and soon they put together a 14-1 blitz to charge into the lead. Rodriguez had two baskets and two free throws during the run, and Nino Williams made a jumper along the left baseline to put K-State up 50-41 with 13:12 left.

The Cowboys responded by pushing the pace in transition, and Nash had a two-handed slam and a pair of layups during an 11-0 comeback. Smart's three-point play off a driving runner along the right side of the lane put OSU back up 56-53 with 6:21 remaining — and fans chanted "One more year!" to the NBA prospect as he hit the free throw.

About 2 minutes later, Smart was picking himself up off the ground after Rodriguez's charge and helping the Cowboys close out the win.

"I don't know if we got tired or tentative or what, but we had opportunities and just didn't take advantage of it," Weber said. "So, it's disappointing for our guys, for everybody involved, but there's a lot of good things that can still happen in March."