Australia’s hopes of reaching the Super 8 stage of the T20 World Cup are all but over after Sri Lanka’s Pathum Nissanka hit a brilliant unbeaten 100 to condemn them to an eight-wicket defeat in Pallekele.

Stunned by Zimbabwe in their second outing on Friday, Australia needed a win to keep their qualification fate in their own hands but it is Sri Lanka who march into the next round.

For Australia to sneak through as the second-placed team from their group, they now need Zimbabwe to lose both of their remaining matches against Ireland and Sri Lanka and then to defeat Oman themselves which would bring net run-rate into play.

Australia’s predicament came from their inability to convert a good start from their openers Travis Head and Mitchell Marsh as they set the home side a target of 182 after a collapse in the second half of their innings.

Despite the feeling Sri Lanka could have a complicated chase on their hands because of a pitch which was slowing down, they eased to victory with the Australian bowling attack lacking any bite in the absence of injured Pat Cummins, Josh Hazlewood and Mitchell Starc.

And the Sri Lanka duo of Nissanka and Kusal Mendis took full advantage.

With wicketkeeper Mendis providing perfect support with a composed 51 from 38 balls, Nissanka brought up his century in 52 balls to take his side past the finish line with an innings that blended brute power and finesse.

Australia had Marsh return after recovering from a groin injury that forced him out of the first two matches and the returning skipper gave his side a solid platform batting alongside Head, who hit a long-overdue half-century off 27 balls.

They powered Australia to 104-0 in 8.2 overs before Head departed for 59 and it marked the beginning of dramatic downturn.

Marsh followed him shortly after with a brisk 54 as they unravelled alarmingly to be bundled out for 181, losing their final five wickets in the space of just seven runs and 14 balls.

With Sri Lanka chasing down the target with ease, the Australians are left clinging to only the slimmest mathematical hope and will watch nervously as Zimbabwe face Ireland on Tuesday.