India held their nerve to seal their place in the World Cup semi-finals after a five-wicket win over defending champions Australia in Ahmedabad.
Australia captain Ricky Ponting scored an inspired 104 after having won the toss and elected to bat first in what could be his final World Cup match as his side posted 260 for six.
The co-hosts were pegged back in their reply after half-centuries from Gautam Gambhir and Sachin Tendulkar, who passed 18,000 ODI runs in the process as their run-chase faltered.
But Yuvraj Singh steered India home with a composed 57 alongside the unflappable Suresh Raina as the hosts clinched victory with 14 balls to spare.
India's win ensures the hotly-anticipated semi-final clash with intense rivals Pakistan on March 30, while Australia's campaign was ended abruptly.
The 1983 champions employed seven bowlers, with Yuvraj Singh, Ravichandran Ashwin and Zaheer Khan claiming two wickets apiece as Australia were restricted to 260.
Brad Haddin chipped in with 53 and David Hussey 38 as the pair partnered Ponting, who may well have ended his one-day career with a century which underlined his class.
Opener Shane Watson fell for 25 after a sluggish start but the Haddin-Ponting partnership yielded 70 brisk runs to steady the boat.
Yuvraj was lurking around and underlined his worth as a part-time bowler by dismissing Haddin and Michael Clarke.
Mike Hussey's stay was cut short by Zaheer but his brother played a cameo in Ponting's company to keep the scoreboard ticking.
Tendulkar led from the front after Virender Sehwag was swiftly dismissed as India's run-chase began, and the Little Master looked set for his 100th international century before he was caught behind off the bowling of Shaun Tait.
India's middle order erred as Gambhir was run out after a comical mix up with Yuvraj, while Virat Kohli and captain MS Dhoni both failed to add significant contributions.
But Yuvraj followed his two wickets with the ball with an innings of assurance, conviction and unwavering belief as he led his side to their target.
Fittingly, the all-rounder hit the winning runs with a flamboyant drive for four through extra-cover, and Australia's incredible run at recent World Cups came to an end.
As a result, the tournament will see a new winner for the first time since 1996, and the semi-final clash between Pakistan and India could hardly be more mouth-watering.
New Zealand and South Africa meet in the third quarter-final on Friday, before Andrew Strauss's England face Sri Lanka in the final last-eight encounter on Saturday.