The Bears (19-10, 7-9 Big 12) led 50-36 after Taurean Prince completed a three-point play with 8:05 left in the game. They didn't make another field goal, but Kenny Chery hit seven consecutive free throws in the final 3 minutes before a miss.
Brady Heslip added 14 points for Baylor, which got a needed victory for its NCAA tournament hopes.
Robert Turner had 12 points for Texas Tech (13-16, 5-11), which had beaten Baylor at home by 10 points.
Baylor shot just 30 percent overall (16 of 53). The Bears had more offensive rebounds than defensive (21 to 19).