Unseeded Marcos Baghdatis reached the final of the Australian Open with a dramatic 3-6 5-7 6-3 6-4 6-4 win over David Nalbandian of Argentina.
Fourth seed Nalbandian had looked in control after taking the first set and holding off Baghdatis in the second.
But the 20-year-old, ranked 54th in the world, clawed back the next two sets.
In the decider, the Cypriot twice came from a break down, and held his nerve after a rain delay, to earn a showdown with Roger Federer or Nicolas Kiefer.
Baghdatis was appearing in his first Grand Slam semi-final after stirring wins over Andy Roddick and Ivan Ljubicic.
And his remarkable victory was met with a huge roar of approval from the crowd at the Rod Laver Arena.
"Everything is like first time here for me - getting to the quarters was a first time and the semis and now I hope it continues on Sunday night"
"It was quite tough," said the 24-year-old. "He's very good player. "I had a lot of chances to win the match, so I can't understand how I missed that opportunity to win it."
Surprise package of the tournament, Baghdatis had struggled early on as Nalbandian started ripping winners from both sides to seal the first set and race to a 5-1 lead in the second.
But he refused to give up, rallying to level at 5-5 before the local fireworks to celebrate Australia Day seemed to affect the young Cypriot's concentration.
Number four seed Nalbandian rattled off the next two games to clinch the set but Baghdatis continued his fightback.
He survived an early break to take the third set and broke Nalbandian for the only time that he needed to in the fourth, holding serve the rest of the way.
Nalbandian led 4-2 in the final set before the former world junior number one reeled off the last four games to secure an astonishing victory.
Baghdatis was serving for the match at 15-15 in the 10th game when rain interrupted play, forcing a 30-minute delay.
"It's amazing," said Baghdatis, who had not made it past the fourth round of his first five Grand Slam events. "I have to wake up, I think, it's just unbelievable.
"It's a dream to play and win this tournament. I'm very proud of myself. It has been an amazing career for me, it's like a story.
"Everything is like the first time here for me. Getting to the quarters was a first time and the semis and now I hope it continues on Sunday night."