Jeremy Lamb had 19 points to lead Connecticut (16-10, 6-8), which fell to 2-3 in the five games coach Jim Calhoun has missed with back problems.
Marquette outran UConn and used their pressure defense to force seven early turnovers to take control of the game.
Marquette, which lost 6-foot-11 center Chris Otule in December and 6-8 Davante Gardner last month, both to knee injuries, had just seven scholarship players available and nobody over 6-7.
But they outrebounded UConn 33-30, including 20-13 in the first half as the built 43-29 lead at the break.
A 3-pointer from Lamb and a dunk by Oriakhi helped the Huskies on a 10-1 run that cut the lead to 48-44.
But after Marquette called a timeout, UConn freshman Ryan Boatright got in Todd Mayo's face and picked up a technical foul. Two free throws and a 3-point shot later the lead was back to 53-44.
A driving layup by Crowder led to UConn center Andre Drummond's fifth foul, and the free throw gave Marquette a 75-63 lead with just under 3 minutes to play.
Johnson-Odom had 16 of his points before intermission and Crowder added 13.
The Golden Eagles used three consecutive fast-break baskets to go up by six points early, then used a 12-2 run to stretch that to 35-22.
A 3-pointer by Johnson-Odom gave Marquette their largest lead at 43-27, before a Roscoe Smith jumper cut the lead back to 14.
Marquette, which has never finished better than fourth place in the Big East, came in tied with Notre Dame for second place in the conference. The top four teams get a double bye in the tournament.
The Golden Eagles have won four of their last five games in Connecticut and three in a row. The road team has won the last five meetings between the two schools.
Connecticut beat DePaul by 26 points on Wednesday, but has now lost seven of its last nine games and has won just four times since Jan. 1.
Coach Jim Calhoun has missed eight games so far this season, three because of an NCAA suspension for recruiting violations and the last five after taking an indefinite medical leave with spinal stenosis. The school has said he will miss at least one more game, Monday night at Villanova.
Spinal stenosis is a narrowing of the spine, normally associated with aging and sometimes with arthritis. Calhoun is currently trying non-surgical treatments, and expects to know if they are successful by the middle of next week.