Cooper scored 18 of his 19 in the second half in 14 minutes and finished 10 for 11 from the foul line altogether.
Devan Cambridge's 3-pointer with 13:08 to play gave Auburn a 40-38 lead it never surrendered. Vanderbilt led 25-23 at halftime.
The Tigers entered ranked 289th nationally among Division I teams in scoring defense, surrendering 76.2 points per game. Auburn had allowed at least 75 points in six straight games going 2-4 during that stretch. They'd also given up 75 or more in eight of their last nine games.
While Auburn (11-10, 5-7 Southeastern Conference) may improve a tad in scoring defense, they have Vanderbilt's (5-10, 1-8) 11-for-22 shooting effort from the foul line to be thankful for.
Auburn faces Kentucky at Lexington on Saturday. The Commodores head to Starkeville to face Mississippi State on Saturday.
For more AP college basketball coverage: https://apnews.com/Collegebasketball and http://twitter.com/AP--Top25
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