Australia set up a showdown with India for a semifinal place at the World Twenty20 after knocking Pakistan out of the tournament with a 21-run win in Mohali. Both teams needed a victory to retain any chance of joining New Zealand in progressing from Group 2 and into the final four. In the end Australia’s victory was comfortable, largely thanks to a pivotal half-century from captain Steve Smith and a quick-fire 44 from the soon-to-retire Shane Watson.

The pair, who put on 74 from just 39 balls, guided Australia from a difficult start to a flourishing finish after Smith had won the toss and opted to bat on a quick pitch. By the end, Pakistan were left ruing allowing their opponents to rack up a sizable total of 193.

And they were repeatedly unable to find a partnership to match Smith and Watson. Several players got starts and threatened to loosen Australia’s grasp, but each time it was fleeting. James Faulkner would finish with the best bowling figures in Australia’s T20 history, with five wickets for 28, largely thanks to taking four wickets from his final two overs to finish Pakistan off. But it was spinner Adam Zampa, who took three wickets last time out against Bangladesh, who got two key wickets, removing Umar Akmal and Shahid Afridi.

For Afridi the palpable disappointment was etched across his face at the conclusion. Following defeat to New Zealand on Tuesday, the Pakistan captain had suggested that the contest with Australia could be his last in international cricket. And at the post-match presentation on Friday, he said that he would go home to consider his future over the coming days. The decision may yet be taken out of his own hands, with the chairman of the Pakistan Cricket Board making clear earlier in the tournament that even if Afridi changed his mind about retiring he would not be staying on as skipper.

If it is the end, it is an ignominious way to bring the curtain down on a distinguished international career lasting almost 20 years. Pakistan have never looked like a convincing unit in this tournament and three defeats from four games shows how far they have fallen in cricket’s shortest format since winning the competition in 2009.

Australia, meanwhile, live to fight another day in their quest to land a first World T20 title. Possessing a better net run-rate than the hosts, a victory against India on Sunday will now see Australia into the semifinals.

Australia had not looked like potential winners when struggling with the bat in a defeat to New Zealand and a nervy win over Bangladesh earlier in the tournament. And there were some worrying signs at the start on Friday, too. The much-discussed batting order had been reconfigured, with Aaron Finch returning to the side to open with Usman Khawaja. But neither could make telling contributions. And, with David Warner going early, too, Australia at one stage were 57-3.

Smith, though, was there to play a captain’s innings. Having been part of a struggling middle order thus far at this World T20, Smith, this time, rotated the strike expertly, while also hitting seven boundaries, all fours. And, following a useful 30 from Glenn Maxwell, Watson showed that he can still inflict plenty of damage. The 34-year-old, who this week announced that he would be retiring from international cricket following this tournament, bludgeoned 44 off just 21 balls, including three sixes.

Having gone down meekly when chasing New Zealand’s 180 in their last match, Pakistan were always up against it hunting the 194 needed to get the win they needed, in conjunction with a narrow Australia victory over India, to progress.

Still, there were moments of encouragement. Sharjeel Khan got going with some typical power hitting, but was not helped by opening partner Ahmed Shehzad needlessly throwing his wicket away. Soon Sharjeel was gone, too, getting a bottom edge onto his own stumps in Faulkner’s first over. After Akmal had gone, Afridi got the Pakistan fans in the crowd on their feet with a couple of big sixes. But his exit, possibly his last on such a stage, after  being deceived into a stumping by Zampa, realistically spelled the end for Pakistan.

Khalid Latif’s 46 was not nearly rapid enough to make a difference, while Shoaib Malik’s 40 was too little too late. Australia bowled expertly down the stretch and look to be growing into the tournament just in time to make Sunday’s clash with India a tantalizing prospect.