Despite not wanting to bat first on a fresh pitch under cloud cover, opener and captain Aaron Finch unleashed the century he'd signaled in previous matches, his 153 from 132 balls powering Australia to 334-7. Finch flowed with Steve Smith for a tournament-high partnership of 173, and they left Glenn Maxwell time to hit a 25-ball 46 not out.
But the Sri Lankans weren't intimidated by the 335 target. They were gung-ho and attacked. Dimuth Karunaratne tried to inspire his side like Finch did Australia, but after he was out for a career-best 97 in the 33rd over, his team collapsed. From 186-2 to 247 all out in 45.5 overs, the last eight wickets fell for 61 runs.
The 11 days since their last match, after two washouts, didn't help, but the batsmen are struggling. Sri Lanka was previously bowled out for 136 by New Zealand and 201 by Afghanistan. The team remains in the top half of the standings, but not for long on this form. England is next up on Friday.
"We need to come up with a plan," Karunaratne said, adding his middle-order batsmen also need to knuckle down. The benefit of playing three matches while Sri Lanka was watching the rain was borne out. Australia was match tough, and adapted to rough patches.
"When you're playing really good cricket, it's nice to be playing all the time," Finch said. "You just get on a roll. You get into playing mode. "We're happy where we're sitting, but definitely time to sit back and assess where we can improve and what we can do over the next couple of weeks to give ourselves the best chance to be standing on the Lord's balcony on the 14th of July (after the final)."
Finch lost the toss for the fifth match in a row and then made all the early running for Australia. Opening partner David Warner, after his century on Wednesday against Pakistan at cozy Taunton, went back in his shell on the open plains of the Oval.
Despite Warner's restraint, Finch's placement together with untidy Sri Lankan fielding helped the openers compile their fourth half-century partnership of this World Cup. They were 80 without loss when Warner was bowled trying to cut spinner Dhananjaya de Silva.
Usman Khawaja was circumspect, too, and Australia went from overs 11-20 without scoring a boundary. He was out trying to up the pace, and it took the arrival of the equally aggressive Smith to free up Finch again.
Finch launched de Silva twice over long on, and reached his hundred off 97 balls with a six over long off. The floodlights came on as if to put more of a spotlight on the skipper. But as soon as he equaled his best ODI score of 153 not out in March against Pakistan, Finch skied Isuru Udana and was caught in the covers in the 43rd over. He banged his bat against his pads and walked off to a deserved ovation.
Smith was out for a 59-ball 73 in the next over to a yorker by Lasith Malinga. Maxwell lashed five boundaries and a six, scoring 46 of Australia's last 61 runs, but it was Sri Lanka which finished on a high, especially Udana, the fast-bowling allrounder, who took the wickets of Finch and Shaun Marsh, claimed two run-outs, and a catch.
That carried over to openers Karunaratne and Kusal Perera, who lashed out at Starc and Cummins. Karunaratne was the more streaky, but he and Perera showed impressive timing and power in their risky approach.
Australia fed them by bowling too short for too long, and the openers raced to 87-0, the highest World Cup score after 10 overs in 20 years. Karunaratne reached his 50 with his seventh boundary, and Perera followed with a 33-ball 50.
Perera, on 52, lost his middle stump to Starc at 115-1, and Karunaratne reined back, consolidating with Kusal Mendis. Karunaratne passed his previous best ODI score of 77 and was set for a maiden century at 97 when he cut Kane Richardson straight to Maxwell in the gully.
At 186-3 in the 33rd over, the air went out of Sri Lanka's charge and wickets were shared around. Starc's four tied him for second on Australia's all-time World Cup list, Richardson claimed three, Cummins two, and Jason Behrendorff, playing in place of Nathan Coulter-Nile whose back stiffened up, claimed a wicket in his World Cup debut.
Australia doesn't play again until Thursday, against Bangladesh.
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