Australia’s fate rests on Sri Lanka following a nervy win over Afghanistan on Friday that didn’t do much to bolster their net run rate.

Glenn Maxwell scored an unbeaten half-century and spinner Adam Zampa took a crucial 2/22 as the defending champions joined New Zealand on seven points after a win by just four runs over the Afghans in Adelaide.

It was not, however, enough to raise their net runrate above that of England, who now need only to beat Sri Lanka in their final Super 12 match in Sydney on Saturday to take the other semi-final berth from the group.

Australia needed to contain the Afghans to 106 runs or fewer to overhaul England’s net run rate. Since they couldn’t, New Zealand, who had earlier in the day beaten Ireland by 35 runs, sealed a place in the semi-finals.

“Afghanistan played really well but luckily we managed to hold them back,” said Maxwell. “They executed well and we couldn’t get away. We’ve put ourselves in this situation but hopefully, the Sri Lankans can do the job for us.”

At one stage in Afghanistan’s response to Australia’s 168/8, it looked like the home side might not even get the win they needed to keep their tournament alive.

Three wickets in Zampa’s fourth over — the first a run out from a Maxwell direct hit — broke a 59-run stand between Gulbadin Naib (39) and Ibrahim Zadran (26) and took the Afghans from a comfortable 99/2 to 99/5.

Rashid Khan revived the innings with four sixes in a battling 48 to keep his team in the chase but he came up just short in the final over and Afghanistan finished on 164/7 to remain winless in the tournament.

Australia had earlier come out to bat with plenty of intent, a much-changed team, and a stand-in captain in Matt Wade after Aaron Finch and Tim David were ruled out by hamstring strains.

Cameron Green and Steve Smith perished cheaply and it was left to David Warner (25), Mitchell Marsh (45) and Maxwell (54) to get the runs.