OMAHA, Neb. -- The face of Creighton (No. 19 ESPN/USA Today, No. 21 AP) disappeared when the Bluejays needed him most.
Weems scored 25 of his career-high 31 points in the second half and Anthony Downing had a career-high 26 points in his first start for the defending Missouri Valley Conference champion Bears (8-5, 1-0).
"They came into our house and punched us in the mouth," Creighton coach Greg McDermott said, "and we didn't do anything about it."
The game was billed as a matchup between McDermott, considered the nation's top mid-major player, against Weems, the reigning MVC player of the year.
The two battled back and forth the first 10 minutes of the second half, then Weems took over.
He scored 17 points in the last 10 minutes while McDermott, guarded by Weems and freshman Christian Kirk, struggled to even get shots. Some of the ones he took were ill-advised.
"Whenever I put it on the floor and tried driving to the hoop, they collapsed," he said. "I feel I let us down. I got in there and threw up some tough shots I shouldn't have taken."
McDermott, averaging 25.4 points for Creighton (10-2, 0-1), had his streak of 20-point games end at 10. He was 8 of 18 from the field.
His 3-pointer with 10:39 left gave the Bluejays a short-lived 51-50 lead. He took only three shots the rest of the way, missing them all.
Weems, by comparison, has had a quiet start to the season. He came in averaging 14.3 points, shooting just 39 percent from the field and with three 20-point games.
Weems made 5 of his last 7 shots from the field as the Bears pulled away late.
McDermott had said before the game that he feared Weems was due to have a breakout game after the Bears had lost five of their last eight.
"I know what I'm capable of doing," Weems said. "I give credit to my coaches to put me in position to be successful and to my teammates for giving me the ball. It's not a one-man thing. It's five guys playing, and we need all 13 or 14 on the roster to be successful."
Downing, a transfer from Independence (Kan.) Community College, had scored in double figures in six of his 12 previous games. He made 11 of 14 shots from the field, including 4 of 6 3-pointers.
"I was really hyped to play in front of all those people," Downing said. "I just stayed aggressive. I don't want to get too high. I wanted to stay calm and play my game."
Ethan Wragge's two free throws tied it at 57 with 6:55 left and got the crowd on its feet. Grant Gibbs could have given the Bluejays the lead after he made a steal and got fouled. But he missed the front end of a 1-and-1, and Michael Bizoukas went the length of the court for a left-handed layup to give the Bears the lead for good.
Downing's 23-footer as the shot clock ran out with 1:11 left gave the Bears a six-point lead.
Jarmar Gulley had 12 points for the Bears.
Missouri State won for the first time in six road games against ranked teams. Preseason MVC favorite Creighton lost at home as a ranked team for the first time in 19 games since 1975.
"Anybody who watched it, it's clear the tougher team won," Greg McDermott said. "They were first to the floor, they were more aggressive on both ends of the floor. They knew where they wanted to get the ball, and they got it there, and we didn't do much to fight it."
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