Terrell Brown Jr. scored 26 points, Emmitt Matthews Jr. added 15 points and 11 rebounds, and Washington held on in the closing seconds for a 60-58 win over Colorado.
Tristan da Silva scored a career-high 22 points, freshman Julian Hammond III added a season-high 14 and Colorado beat Washington 78-64 for its fifth consecutive win.
No. 5 Texas A&M and Colorado were once Big 12 adversaries. The Aggies and Buffaloes are now in different conferences as they meet for the first time since 2009 at Empower Field in Denver.
The 10th-ranked Oregon State Beavers snap a three-game losing streak with a 79-52 rout of the Colorado Buffaloes behind junior guard Aleah Goodman's big night.
Steve Montez threw for a touchdown and led a long final drive from the shadow of his own end zone to run out the clock as Colorado beat Washington 20-14.