Cash's three-point play snapped a tie with 14 seconds left as the Shock won their fourth straight, 72-68 over the Indiana Fever.
Tamika Catchings made two free throws with 39 seconds to go, forging a 65-65 tie. After a timeout, Cash missed a jumper, but Elaine Powell came up with the offensive rebound and fed Cash for a basket as she was fouled by Kelly Schumacher.
Cash's free throw made it 68-65, Indiana committed a turnover and the Shock made 4-of-4 from the line in the final 12 seconds to seal the win -- their second this week over the Fever.
Ruth Riley scored 26 points on 9-of-11 shooting to lead Detroit and Cash netted 22 for Detroit, which was 27-of-35 from the line. Indiana went 10-of-12.
Natalie Williams scored 19 points and Catchings added 15 for Indiana, which shot 37 percent (25-of-67).