MELBOURNE, Australia -- What happened to the Roger Federer who was so dominant in the past three months?
Well, he showed up early against Gilles Simon on a chilly Wednesday night in Melbourne, flawlessly taking a two-set lead. Federer was nearly untouchable on serve, confidently hit through his groundstrokes and moved forward when given the chance. In short, all the things he was doing under newish co-coach Paul Annacone. The kind of things that led to a 27-2 record in his past 29 matches. Simon was no slouch, either, one of the few players to hold a winning record against the 16-time Grand Slam champion at 2-0.
Then Federer dipped. And yes, it was a case of the Swiss faltering and Simon upping his level, not simply the latter. Having taken proceedings to a fifth set and with the momentum, Simon lost the decider rather than Federer winning it. The final score read 6-2, 6-3, 4-6, 4-6, 6-3.
"Today I got lucky," Federer said in an on-court interview, probably meaning it.
U.S. Davis Cup captain Jim Courier, commentating for host broadcaster Channel 7, was at a loss to describe the bizarre turnaround -- probably along with viewers around the world.
Federer looked rattled in the third and fourth sets. He produced shanks on his backhand, which before the second round had looked as good as ever, and was tentative on his forehand. Courier astutely noted that the mis-hits were strange, given that Simon hits a relatively flat ball.
Federer, who has been driving through the backhand on returns since the fall, reverted to using the slice as the match got tighter. He committed an inflated 27 unforced errors in the third and fourth.
Simon was on somewhat of a roll himself, winning a title in Sydney last week to remind us he's a former top-10 player. He moves brilliantly, can turn defense into offense a la Andy Murray and owns a great two-handed backhand. Ultimately, he'll be kicking himself for the way he dropped serve in the final set, blowing a 40-15 advantage and making two cheap errors at 2-3.
"Gilles started to work his way into the match late in the second set and really stepped it up in the third," ESPN analyst Darren Cahill said. "It may have taken Roger a bit by surprise. Instead of controlling the baseline points, Roger was pushed back to neutral more often than not, and Simon was pouncing on anything short. Roger settled down on his backhand in the fifth."
So, Federer's Grand Slam quarterfinal streak remains intact, and he still hasn't lost a majors match when leading after two sets -- 166-0.
But this doesn't bode well for Federer for the rest of the tournament. The air of invincibility he was rebuilding took a hit. Xavier Malisse, the highly talented Belgian Federer meets in the third round, surely got a boost. Maybe Novak Djokovic, who probably will meet Federer in the semifinals, did, too. A little self-doubt might arise for Federer himself.
Federer played early-round five-set thrillers at the Australian Open in 2008 and 2009. Ominously for him, he failed to win the tournament both years.
Ravi Ubha is a frequent contributor to ESPN.com.