Center Leroy Combs scored a season-high 34 points to help Oklahoma State upset No. 12 Missouri, 93-92, in double overtime for the Big Eight Conference tournament championship yesterday in Kansas City, Mo.

Combs was named the most valuable player as the Cowboys (24-6) clinched the Big Eight's automatic berth in the NCAA tournament. Combs made 11 of 16 field goal attempts and 12 of 14 free throws; he also had 11 rebounds.

Missouri (26-7) lost its first in seven games; it was the Cowboys' second straight victory over Missouri after losing nine in a row.

Oklahoma State trailed only once after guard Lorenza Andrews made a twisting layup with one second remaining in the first overtime to tie the game at 81. In the second overtime, Combs made two free throws, but Missouri's Steve Stipanovich tied the game with a basket.

After a free throw by Charles Williams made it 84-83, Missouri regained the lead on a layup by Ron Jones. The Cowboys took the lead for good at 88-85 on two free throws by Williams and Andrews' bank shot.

Missouri's Jon Sundvold missed 16 of 22 shots, including a jumper that could have tied the game with eight seconds left in the second overtime. But his coach, Norm Stewart, defended him: "He's shot so many in the basket to win games. He's human, and everyone's going to have games like that--and today was his."