Five thoughts after Djokovic's titanic upset of Federer

Novak Djokovic has beaten Roger Federer once before, but his straight-sets win in the Aussie semis may be his biggest win yet. Jessica Kluetmeier/SI

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MELBOURNE, Australia -- Five thoughts after watching Novak Djokovic take down Roger Federer on Friday in the Australian Open semifinals:

Djokovic is for real

Yes, we knew that already. This event, after all, marked his fourth straight Grand Slam semifinal. But the 20-year-old went all Jim Collins on us -- good to great -- Friday night. Djokovic put a beating on the two-time defending champ, outplaying him from the baseline, out-serving him and frustrating him with his defense.

But beyond that, Djokovic played opportunistic tennis. When he needed to break, he broke. When he needed to hold, he held. Down three break points in a potential momentum-changing game of the third set, Djokovic fired two aces and survived. He induced an error on match point. This was the sort of poised "step up" performance that defines champions.

Even the Great Ones pay for a lack of preparation

Federer played no tune-up events to start the year. Which would have been OK, except that when a stomach ailment prevented him from playing in the Kooyong pre-tournament exhibition, he entered this event with no match play in 2008. He breezed through his first two rounds, but as the tournament wore on, he looked torpid and stripped of energy.

He served his way out a five-setter against Janko Tipsarevic in round three and then stayed alive for two more rounds. But tonight he played "tired tennis." By his own admission, he was a step slow. He made scads of inexplicable errors. Now history will have to wait.

Federer has a new rival

Rafael Nadal has a winning record against Federer. But the two seem to have reached a certain détente: "You rule the clay; I rule everything else." What's more, Nadal is filled with deference for Federer; and vice versa.

The dynamic between Federer and Djokovic is different. Even before Federer bristled at Djokovic's impersonations, he was noticeably tepid when speaking about his game.

Likewise, Djokovic has been outspoken about his ambitions to topple Federer and keeps the praise to a minimum. On the court, you'll notice he's not clapping Federer's winners or gushing "too good," as other players do. He's the rare player willing to stare down The Mighty Fed. And it worked Friday.

Defense wins championships

We saw this on Thursday with Jo-Wilfried Tsonga as well. Much as the crowd loves the spectacular shot-making and the flailing winners; matches are often won by simply keeping the rally alive. Djokovic did a terrific job prolonging points with his movement and scrambling. (Now if he would just stop giving away points with ill-advised drop shots.)

Bring on the final

Neither of the top two players are left in the draw. For the first time in three years, Federer has missed a final. And Djokovic's opponent on Sunday, Tsonga, came in ranked No. 38 at the start of the tournament. Yet there's plenty of anticipation for Sunday's winner-take-all match.

Tsonga has been absolutely electrifying, a versatile player who combines brute power with feathery touch. The Australian Open has a history of "fluke finalists" (Arnaud Clément, Thomas Johansson, Rainer Schüttler, even Fernando González).

But one senses that Tsonga's emergence is legit. Djokovic, meanwhile, confirmed tonight that he's a future champion. And the future could be as close as three days from now.