Minnesota junior Ryan Lewis' stunning pin of Oklahoma State's top-ranked Johnny Thompson at 133 pounds lifted the No. 1 Gophers to a 21-12 win over No. 2 Oklahoma State on Sunday afternoon before 5,000 fans at Gallagher-Iba Arena in Stillwater, Okla.    Thompson, who finished second in the nation as a freshman last season, was pinned with nine seconds left in the bout.    Minnesota, the defending national champions, won 6 of 10 bouts to earn the win.    The Gophers also received wins from Chad Erikson (141), Jared Lawrence (149), Luke Becker (157), Jacob Volkmann (174) and Owen Elzen (197).    Becker, ranked third, rolled to a 13-6 win over No. 2 Shane Roller of Oklahoma State. Becker avenged a loss to Roller in the third-place match of last year's NCAA meet.    Volkmann, ranked third, edged OSU's No. 5 Ty Wilcox 3-1 in overtime.    Oklahoma State received wins from Skylar Holman (125), Tyrone Lewis (165), Pat Popolizio (184) and James Huml (heavyweight).    Holman, ranked third, topped No. 2 Leroy Vega of Minneosta 6-4. Lewis, ranked second, held off No. 10 John Hardy of Minnesota 3-2. Popolizio, ranked third, topped No. 7 Damion Hahn of Minnesota 2-1. Huml, ranked 16th, upset No. 5 Garrett Lowney of Minnesota 3-2.    Third-ranked Oklahoma rolled to a pair of dual-meet wins over Rider (36-6) and Rutgers (38-3).    Fourth-ranked Michigan rolled to the team championship at the Cliff Keen Invitational on Friday and Saturday in Las Vegas. The Wolverines had 163 points while runner-up West Virginia had 127.    Fresno State's Stephen Abas, who just returned from the World Championships, rolled to his fourth straight title in Vegas. He was named the meet's Outstanding Wrestler.    The top-ranked Abas, a two-time NCAA champion, pounded No. 5 Jason Powell of Nebraska 13-2 in the finals. Powell pinned No. 4 A.J. Grant of Michigan in the semifinals.    Other champions in Vegas included Clarion's Rad Martinez (133), Cal Poly's Cedric Haymon (141), Harvard's Jesse Jantzen (149), Nebraska's Bryan Snyder (157), West Virginia's Tom McMath (165), Michigan's Otto Olson (174) and Andy Hrovat (184), Lehigh's Jon Trenge (197), and Air Force's Kevin Hoy (heavyweight).    The No. 5 Iowa Hawkeyes completed their Eastern swing with three dual-meet wins over the weekend. Iowa beat Penn 21-12 on Friday before downing Princeton 36-7 and Hofstra 24-15 on Saturday.    The No. 6 Iowa State Cyclones breezed to four dual-meet wins on Saturday to capture the Simpson Duals in Indianola, Iowa. ISU beat Augustana (Ill.) 46-4, Cornell 36-3, Coe 32-12 and Simpson 37-12.    On Sunday, Iowa State edged Wisconsin 24-21 at Hilton Coliseum in Ames.    ISU's Cael Sanderson went 5-0 over the weekend at 197 and is now 132-0 in his career.    Each team won five matches, but Iowa State (7-0) got bonus points in four of its victories and that was the difference against Wisconsin.    Sanderson, ranked No. 1 at 197 pounds, pinned Jareck Horton in 2 minutes, 34 seconds. It was the 47th career pin for Sanderson, who is 13-0 this season. ISU's Joe Heskett, the top-ranked wrestler at 165, pinned Ryan Lewis in 5:53. He is also 13-0.