NORMAN, Okla. (AP) -- Under first-year coach Lon Kruger, the focus all season for Oklahoma has been getting better each day.

At home on Saturday, the Sooners took a giant step forward with an 82-73 victory over No. 18 Kansas State.

"It was a huge game for us," Kruger said. "I'm really proud of the guys. I really thought they battled from start to finish. What made it more special is Kansas State is a legitimate top 20 team."

Oklahoma (11-5, 1-3 in Big 12) led the entire game but had to fend off several Kansas State runs while being outrebounded 44-24.

Andrew Fitzgerald led Oklahoma with 21 points, while Romero Osby and Steven Pledger both had 18 and Cameron Clark added 10. It was Oklahoma's first Big 12 Conference win after an 0-3 start.

"We just came out and shot the ball with confidence," Fitzgerald said. "It all comes down to us working hard at practice."

Rodney McGruder had 19 points to lead Kansas State (12-4, 1-3) while Nino Williams and Jeremy Jones each added 12 points.

A former All-Big Eight point guard for Kansas State in his playing days, Kruger took more pleasure in watching his team stand up to Kansas State's comebacks than beating his alma mater.

Oklahoma shot 55 percent from the field overall and 70 percent in the second half. Kansas State made things a little easier, contributing 19 turnovers.

"Making shots is the remedy when you're not doing other things well," Kruger said. "A lot of guys stepped forward as you have to do to beat a good team."

Trailing by nine points at halftime, Kansas State fell behind by as many as 18 in the second half.

The Wildcats cut the deficit to six with 57 seconds remaining but were forced to foul late and the Sooners made four of six free throws over the final 1:21.

Oklahoma opened with a 7-0 run, prompting Kansas State Coach Frank Martin to call a timeout just 1:42 into the game. The Sooners led by as many as 12 points in the first half as Kansas State struggled to find offensive consistency while shooting 33 percent.

Leading by 18 points with 8:27 remaining in the second half it looked like Oklahoma would run away but two 3-pointers from Will Spradling and a basket from Williams as he was falling down cut the deficit to eight.

"We didn't come out with any energy. We came out flat," said Spradling, who finished with 11 points. "If you're playing in anybody else's gym and come out flat you're going to get punches. When we got punched we didn't hit them back."

The conference's best rebounding team, Oklahoma was outrebounded for only the third time this season.

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