India v Australia : Three key World Cup battles
India and Australia clash in the standout game of the World Cup so far on Sunday, with Virat Kohli's men desperate to lay down a marker against the five-time champions.
In the past five editions of the tournament, India are the only team to have denied the Australians the trophy, on home soil in 2011.
Look at three key battles ahead of the match at the Oval.
Kohli v Starc
Virat Kohli is the world's top-ranked batsman in one-day internationals and Tests while Mitchell Starc is Australia's left-arm pace spearhead.
Kohli was out for just 18 in India's opening game in Southampton but averages more than 53 against Australia in ODIs.
Starc, who took five wickets in Australia's win over the West Indies, will be handed the responsibility of taking early wickets, with Kohli the prized scalp.
"When he's got his rhythm and his form is good, he's definitely the best around -- I think that is without question," said former Australia captain Allan Border, who led the team to their 1987 World Cup triumph.
Warner v Bumrah
Swashbuckling Australian opener David Warner has returned from his ball-tampering ban in style.
After topping the run charts in the Indian Premier League, Warner smashed an unbeaten 89 in Australia's opening World Cup win over Afghanistan.
But the left-handed batsman will be up against an Indian paceman who tops the ODI bowling rankings, with 87 wickets in 50 matches.
Bumrah set the tone for India's win against South Africa on Wednesday with his two early strikes.
South African opener Hashim Amla called him "one hell of a bowler" after the 25-year-old quick sent the veteran batsman packing for six on a cloudy Southampton morning.
Zampa v Chahal
Adam Zampa is no Shane Warne but is expected to be Australia's key spin hope against India.
Fifteen of the leg-spinner's 64 ODI wickets have come against India since his debut in 2016 and variations including the googly and the straight ball make up for his lack of prodigious turn.
His Indian counterpart, Yuzvendra Chahal, is seen as Kohli's go-to spinner along with spin partner Kuldeep Yadav.
Chahal returned figures of 4-51 against South Africa and the former chess player will be looking to plot Australia's downfall.
"Chess has taught me patience and planning," he said. "When you play chess you normally plan 15 to 16 moves in advance."