South Africa will play Friday's vital World Twenty20 Group 1 match against West Indies without all-rounder JP Duminy who has been ruled out with a hamstring strain. Duminy picked up the injury while fielding in Sunday's 37-run victory over Afghanistan and will be a loss for the side with bat and ball. "The scans which were done Monday confirmed our clinical suspicion of a hamstring strain which means that he will be ruled out of Friday's game against the West Indies in Nagpur," team manager Mohammed Moosajee said in a Cricket South Africa statement Tuesday. "The plan is to try and get him ready for our last round-robin match against Sri Lanka in Delhi Sunday." Duminy has scored 83 runs from 48 balls in the competition without being dismissed and took 1-31 in three overs in the two-wicket defeat by England in South Africa's opening game. The 31-year-old is his country's leading scorer in Twenty20 Internationals with 1,654 runs in 70 matches, fourth on the all-time list headed by New Zealand's Brendon McCullum. Smith warns Australia Australian skipper Steve Smith warned his side faced defeat in coming matches unless it improved after its three-wicket win over Bangladesh in Bangalore Monday. Opener Usman Khawaja hit a quick-fire half-century as Australia successfully chased down Bangladesh's total of 156 for five, with nine balls to spare. The victory puts Australia's bid for a first ever World T20 trophy back on track after the top-ranked Test side lost to New Zealand in the northern hill station of Dharamsala in its opening match. But Smith said the Australians needed to adapt better to different playing conditions if it was going to defeat Pakistan Friday, before taking on red-hot title favorite India for a place in the semifinals. "We haven't been good enough in the middle overs," said Smith. "We've had a bit of travel, but it's not an excuse." "Pakistan and India play well in these conditions and we have to do better. Our players have to adapt better (to different grounds)," he said. Australian spinner Adam Zampa, who took three wickets, his first in T20 internationals, said the side had been disappointed to lose to New Zealand. "The equation for us is pretty simple now, win every game," Zampa, named Man of the Match, said, adding that he expected an equally tough battle with both Pakistan and India.