Former world No.1 Marat Safin's stunning comeback from injury will extend into the Australian Open men's final after he upset defending champion Andre Agassi in a semi-final classic at Melbourne Park.

The unseeded Russian beat fourth seed Agassi 7-6 (8-6) 7-6 (8-6) 5-7 1-6 6-3 in a high-quality 3hr 42min match, ending the American's five-year 26-match unbeaten streak in the tournament.

Agassi fought back from two sets down after looking down and out.

The American failed to convert set points in both tie-breaks in the opening two sets as Safin looked poised to power to a straight sets victory.

After Agassi arm-wrestled a break out of Safin in the final game of the third set to win it, two dubious line calls against the Russian early in the fourth set turned the game on its head.

Safin lost concentration and eventually the set as Agassi looked set to produce one of the great grand slam comebacks.

But the high-quality game Safin played in the first two sets emerged in the fourth game of the final set as he broke Agassi to take a 3-1 lead, holding the advantage to the finish.

Safin served 33 aces for the match and didn't serve a double fault.

It continued Safin's dream return from a wrist injury which forced him out for much of 2003.

The 24-year-old eliminated world No.1 Andy Roddick in the quarter-finals before claiming Agassi's scalp.

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