IT took an incredible comeback to end an incredible comeback. It took a greater player to defeat a great player.
There are a range of reasons why the great Roger Federer is playing on Sunday night in the final and Stan Wawrinka, who has won three majors since Fed's last grand slam title in 2012, is not.
But the elephant in this Swiss chalet can't be ignored: that Federer beats his compatriot nearly every time. This time, it took five topsy-turvy sets, 7-5 6-3 1-6 4-6 6-3, in a semi-final that exceeded the considerable hype and will be long remembered.
Consider the situation. Federer was up two sets to love, cruising majestically to the final. Stan, a man with little to lose, takes a time out, supposedly for his sore knee but succeeds in utterly shifting the momentum - a contentious tactic that Federer would reprise at the end of the fourth.
"Stan took it," said Federer, referring to the first medical time-out, when asked about his own fourth-set disappearance for an unspecified upper leg injury that had bothered Roger since early in the tournament. "Hopefully Stan won't be mad."
Wawrinka, who had been landing every blow from the back court and serving explosively, had Federer down break point early in the fifth. Federer was tiring, his second serve losing velocity.
The traffic was one way - Wawrinka's - and Federer suddenly seemed like a 35-year-old who hadn't played a real event for six months. He was hanging on by his fingernails. If this was the boxing ring, he would have cuddled his friend and clung to the ropes.
Yet, somehow, Federer won the fifth set. Watching them, this seemed improbable. Wawrinka was serving harder, hitting bigger and, while his knee might have been sore, he had energy.
Federer faced breaks points at 1-1 and at 2-2 in that final set.
In a matter of a handful of points, though, Federer went from the brink of blowing a two-sets-to-love lead to resuming normal transmission for the Swiss derby. Without warning, against the flow, he broke Wawrinka's serve for a 4-2 lead.
So the third act of this great drama belonged to Federer.
Whether it's styles and match-ups or pure psychology, Federer suddenly reasserted his dominance over Wawrinka. At the very end, a struggle had reverted back to a stroll.
Federer, who keeps surprising himself in his extraordinary renaissance in Melbourne, has owned Wawrinka even more than his potential opponent in the final, Rafael Nadal, has owned the otherwise incomparable Federer, as the 19-3 record between the two Swiss men illustrates.
Federer's recent history - not having played in an ATP tournament for six months, having not won a major since 2012 (in which time Wawrinka has won all three of his grand slam titles) - clearly counted for less than the history between the players.
This brings us to the final and the question that must be posed of the sublime Roger Federer: Does he really want to play Rafael Nadal in the final?
Federer called Nadal "the biggest challenge" and pledged that he would "leave it all out there", even if he did not play for five months.
The record - 23-11 in Rafa's favour and a one-sided 9-2 in grand slam events - would suggest Roger should be on bended knee, praying that Grigor Dimitrov takes out his nemesis, as Novak Djokovic and Andy Murray were conveniently removed.
That was the question put to Mats Wilander, the former No.1 and seven-slam winner, just before the match. Wilander took the contrary view - that Federer would want Nadal, and should welcome the opportunity to redress this persistent, solitary blight on an otherwise perfect career.
"It (victory) will erase a decade of history," Wilander said.
John McEnroe noted that, for all that Federer and Nadal have accomplished, "this could be the sweetest title of them all".
Sweet for the victor. Sour for the vanquished. For Federer, perhaps, discovering he can still do it is satisfaction enough.
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