Luke Wright hit 66 off 39 balls as Sussex chased down a target of 152 for a five-wicket win against Glamorgan in the NatWest T20 Blast.
Opening batsman Wright led the way with seven fours and three sixes before Matt Machan's 33 not out saw Sussex home with nine deliveries to spare.
Glamorgan had earlier made 151-8 after opting to bat first at Hove.
Jacques Rudolph's 62 was the top score and Murray Goodwin provided some aggression further down the order with a 24-ball 35.
Sussex leg-spinner Will Beer claimed 3-14 - all top-order wickets - from his four overs, and later hit the winning runs.
The result dents Glamorgan's hopes of progressing to the quarter-finals from the South Group and keeps Sussex's hopes alive, mathematically at least.
The Welsh county remain in third place but have played more games than the two teams immediately below them, Surrey and Somerset, while Sussex's move up to sixth, two points outside a qualification spot.