Yuvraj turns on his six appeal to shock Australia

Ruled out of Thursday's epic triumph over South Africa with tendinitis of the elbow, Yuvraj returned and hammered a brilliant 70 off only 30 balls to help India reach a competitive 188 for five after winning the toss.

India's Shanthakumaran Sreesanth (2nd L) is congratulated by his team mates (L-R) Robin Uthappa, Mahendra Dhoni and Yuvraj Singh after he dismissed Australia's Matthew Hayden

It was a target beyond Australia, who were restricted to 173 for seven in reply, to set up a potentially thrilling final at Johannesburg on Monday against arch-rivals Pakistan.

Australia had seemed on track to overhaul India's total while Matthew Hayden and Andrew Symonds shared a 66-run third wicket stand off only 36 balls.

But the loss of three wickets in as many overs effectively ended their challenge and when Mike Hussey, batting with a runner after suffering a suspected hamstring injury, was caught in the deep by Yuvraj in the final over the celebrations began.

Indian seamer Sreesanth had given his side hope of setting up the all-Asian final by bowling stand-in captain Adam Gilchrist - and soon after Irfan Pathan had Brad Hodge caught at short fine leg.

That brought close friends Matthew Hayden and Symonds together and their stand appeared to put Australia back on course to add the Twenty20 crown to their World Cup and ICC Champions Trophy successes.

But with 54 required for victory with five overs remaining, Sreesanth returned to shatter Hayden's stumps after he had hit four fours and four sixes in his 62 off 47 balls.

Two overs later Irfan also struck by bowling Symonds for 43 off 26 balls to swing the momentum firmly in India's direction and leave Australia needing 22 off the final over.

It was beyond even the talents included in Australia's line-up and instead India, possibly the last country to embrace this format of cricket, began preparing for Monday's final.

Yuvraj had earlier given another startling display of his strokeplay, hitting five fours and five sixes to show little sign of discomfort from his elbow by picking up where he left off in his last match against England, when he became only the fourth man in history to hammer six sixes in an over.

Australia's Matthew Hayden (R) walks off the field after being bowled by India's Shanthakumaran Sreesanth

Yuvraj signalled his intent from the very start of his innings, pulling Stuart Clark for six over midwicket, helping India add 96 runs in their final seven overs.

He was finally out in the 18th over of the innings, caught in the deep by Hussey off Michael Clarke's left-arm spin, having previously dominated an 84-run stand off 40 balls with Robin Uthappa.

Captain Mahendra Dhoni weighed in with 36 off 18 balls to leave Australia, desperate to add the Twenty20 crown to their one-day successes in the World Cup and Champions Trophy, needing a major effort to meet Pakistan in Monday's final.

India had begun their innings cautiously and were restricted 37 runs in the first six overs of fielding restrictions with Mitchell Johnson claiming wickets in successive overs to remove openers Gautam Gambhir and Virender Sehwag.

His efforts united Yuvraj and Uthappa in a stunning display of hitting, which saw them claim 19 off the first over from Symonds and 21 off a further over from Stuart Clark.

Uthappa was run out after a mix-up with Dhoni for a quickfire 34 off 28 balls before Yuvraj attempted one big hit too many as three wickets fell in the final five overs.

But there efforts were still enough to complete a deserved triumph to leave the inaugural tournament with as fiercely competitive a final as they could have wished for at the start of the tournament.