Glamorgan's trio of current and former South Africa internationals, David Miller, Jacques Rudolph and Colin Ingram, led their side to a 25-run NatWest T20 Blast win over previously unbeaten Gloucestershire at Bristol.

Miller marked his debut for the county with a 32-ball half-century, featuring four fours and three sixes, as the visitors ran up 176 for 5 after losing the toss. Rudolph contributed 51 off 46 deliveries, while Thisara Perera was the pick of the Gloucestershire attack with 2 for 25.

Ingram then conceded just 18 runs from his four overs of legspin to help restrict Gloucestershire to 151 for 7 in reply. Michael Klinger top-scored with 52 and Michael Hogan claimed two wickets. Victory saw the visitors leapfrog their opponents in the South Group, drawing level with leaders Surrey on nine points.

The Glamorgan innings had begun sketchily on a strange-coloured pitch that looked green in the main, but worn at the edges. After Aneurin Donald had departed early, Ingram had an escape on 1 when dropped by Jack Taylor at deep-square off his brother Matt in the fourth over.

It looked like proving an expensive miss when the dangerous Ingram smacked the first six of the game off David Payne. But on 18 he top-edged an attempted pull shot and skied a return catch to Perera.

At the end of the six-over Powerplay Glamorgan were 41 for 2. It was then that Miller went on the charge, hoisting consecutive sixes off Jack Taylor in what proved the offspinner's only over.

Perera bowled well to keep a check on the scoring rate, but the 11th over, sent down by Matt Taylor, saw Miller strike a six and a four before Rudolph helped himself to successive boundaries. Miller went to his half-century in the 15th over, but the next delivery from Payne saw him well caught by Kieran Noema-Barnett at mid-on to end an impressive innings of 50.

Rudolph moved to his fifty off 44 balls, with four fours and a six, but then drilled a straightforward catch to Benny Howell at long-off to give Perera his second wicket. The Sri Lankan bowled full in the closing overs and was unlucky to concede a couple of streaky boundaries. Chris Cooke fell cheaply to Noema-Barnett, but Graham Wagg and Craig Meschede ensured Glamorgan of a competitive total.

It looked even better when Michael Hogan bowled Phil Mustard for 2 in the third over of Gloucestershire's reply. But Ian Cockbain was in prime form as he and Klinger took the score to 48 for 1 at the end of the Powerplay.

Cockbain's bright cameo ended on 25 when Craig Meschede deceived him with a cutter and the ball went straight up to be taken by wicketkeeper Cooke. George Hankins soon followed for a duck, caught at short third-man attempting a reverse scoop off a gentle long-hop from Ingram, who then conceded only three from his second over.

At the halfway stage of their innings Gloucestershire were becalmed on 65 for 3. Klinger went on the attack, hitting a straight six and a four to third-man off successive balls from Meschede.

Another straight six from Klinger, off Timm van der Gugten, raised home voices in a 4000 crowd and a second maximum in the over took the Gloucestershire skipper to fifty off 33 balls, with four sixes. But the bowler responded with a slower delivery that bowled the experienced Aussie, a hammer blow to Gloucestershire hopes.

Jack Taylor smacked a six and a four off Wagg, who then had him caught at long-off to claim his 100th T20 wicket, as Glamorgan closed in on a well-earned success.