The Lions were chasing 173 for victory and Gayle belted six fours and two sixes as he scored a belligerent 56 off 38 balls. He and Jean Symes added 89 off 68 balls after the hosts were struggling on 36 for three in the fourth over, steering them to victory with seven balls to spare as Thami Tsolekile (23* off 12) hit a couple of sixes in the penultimate over to clinch the win.
Symes compiled a beautifully-paced 58 not out off 50 balls, with four fours and two sixes, and played the perfect foil to Gayle, who showed what a big drawcard he is going to be over the next month.
The West Indian left-hander took a while to get going, but was just beginning to break free, having completed his half-century off 35 balls, when Prenelan Subrayen bowled him in the 14th over.
The Lions still needed 48 off the last six overs, but the Dolphins were unable to restrict Symes and Tsolekile, who completed a comfortable victory over the defending champions.
The Dolphins had to break free from their own poor start after winning the toss and electing to bat first, Cameron Delport falling first ball to Lonwabo Tsotsobe, who seems to be well and truly over his long-term injury niggles, and Morne van Wyk (5) being trapped lbw by Hardus Viljoen’s first delivery.
The Dolphins were 27 for two in the fourth over and desperately needed the stand of 71 off 45 balls between Cody Chetty and Vaughn van Jaarsveld.
Van Jaarsveld stood up from a painful blow amidships from Chris Morris to slap the fast bowler for four and six in the seventh over as the Dolphins passed 50, and Chetty completed a 32-ball half-century with five fours and three sixes.
But the introduction of Gayle with his flat and crafty off-spin derailed the Dolphins progress.
The tall 35-year-old claimed wickets in each of his four overs: Van Jaarsveld (40 off 25) mistimed a lofted straight drive to long-on, Jonathan Vandiar (8) and Khaya Zondo (5) both walked across their stumps and missed sweeps to be given out lbw, and Chetty top-edged a sweep to long-on to fall for a classy 68 off 44 balls.
That allowed fast bowlers Viljoen and Morris to gain access to the lower-order and they wrapped up the innings in style as the Dolphins scored 37 for four in the last four overs.
Viljoen returned in the penultimate over to remove the dangerous Subrayen for 26 off 13 balls and Morris claimed two wickets in the final over to leave the Dolphins short of a winning target on 172 for nine.
Gayle finished with four for 36 to claim the bowler of the match award, but Viljoen returned the best figures of two for 14 in three overs, while wrist-spinner Eddie Leie also managed to frustrate the Dolphins in tandem with Gayle.