Melbourne: Opener Pathum Nissanka was the shining light with 46 as Sri Lanka collapsed to 139 for eight in the fourth Twenty20 clash against Australia at the Melbourne Cricket Ground on Friday. With the home side having an unassailable 3-0 lead in the five-match series, they rested bowling kingpins Josh Hazlewood, Pat Cummins and Mitchell Starc. It left Jhye Richardson, Daniel Sams and Kane Richardson to shoulder the pace load, but Sri Lanka could not fully exploit the weakened attack after being put in to bat. They made an aggressive start, but tight bowling from spinners Ashton Agar and Adam Zampa blunted the run rate before a late collapse saw six wickets fall for 12 runs in the space of 21 deliveries. Both Richardsons took two wickets each. With nothing to lose, Nissanka and Danushka Gunathilaka began aggressively, whacking 35 from the first four overs. It was their best start of the series, with improved running between the wicket as they worked ones and twos. But the inconsistent Gunathilaka didn’t last, caught by Aaron Finch for 17 going for a slog when Agar was brought into the attack. The unflappable Nissanka helped steer them to 73 for one at the halfway mark alongside Kusal Mendis, who hit two big sixes as he raced to 27 off 21 balls, before falling victim to a superb run-out by Glenn Maxwell. But the runs began drying up as the spinners took control, restricting them to just 31 off the next five overs. Charith Asalanka (22) fell to Jhye Richardson and he was followed three runs later by Nissanka, stumped by Matthew Wade off Zampa, sparking the collapse. Dinesh Chandimal (2), skipper Dasun Shanaka (1), Dushmantha Chameera (1) and Maheesh Theekshana (3) all quickly followed before they smacked 17 much-needed runs from the last over off Kane Richardson.