A perfect storm of factors caused Federer to drop his third straight match at this juncture in Melbourne, and he will undoubtedly bounce back to have yet another exceptional 2013 campaign.
Murray had not dropped a set the entire tournament leading up to his 20th career matchup with arguably the greatest tennis player ever. Meanwhile, a newly confident Jo-Wilfried Tsonga nearly bounced Federer in the quarterfinals before Fed-Ex rallied to a five-set victory.
ESPN Stats and Info pointed out a key detail in this unprecedentedly grueling stretch of tennis for the 31-year-old:
Roger Federer is playing back-to-back five-set matches for the first time in his career.— ESPN Stats & Info (@ESPNStatsInfo) January 25, 2013
After a ferocious comeback to dominate the fourth set tiebreaker against Murray 7-2, he simply ran out of steam at the end.
It also was a bit of an off day for Federer, who was more of a victim of Murray's brilliance than his own shortcomings. The 25-year-old Murray also had fresher legs, courtesy of an easier Open draw.
The victor in all of these two players' previous encounters had the edge in a key statistic: percentage of second serve points won. That was again the case on Friday, with Murray winning 63 percent of his and Federer managing just 42 percent in that category himself.
The typically prolific groundstrokes that define Federer's game weren't as effective against the upstart Murray, whose outstanding fitness and power translates very well to the hardcourt.
Long rallies weren't sustainable for the tired Federer, who had to press more than usual and try to shorten points. That led to an uncharacteristic 60 unforced errors to go with just 43 winners.
Not always consistent with his serve, this was a particularly stellar performance from Murray, who delivered 21 aces to counter Federer's mere five.
It makes sense that more serves got by Federer than usual. He was simply fatigued from the Tsonga match, and had his proverbial "B-game." Even that is good enough to beat even the best players in the world like Murray—it just wasn't to be on this day.
The Australian Open was also Federer's 2013 debut, so he isn't exactly in the best shape he could possibly be in. Meanwhile, Murray played at the ATP Brisbane International, where he emerged victorious and had recent competitive success to build on.
Does Roger Federer's loss at the Australian Open signal his decline?
This was just a bad matchup from the beginning, not only from a circumstantial standpoint but also due to the demanding style with which Murray plays. It was unsustainable for five sets, despite King Roger's best efforts.
Murray improved to 11-9 against Federer all time, including finally breaking through in a major event.
But the king has not yet been slain. This was Federer's 10th straight semifinal appearance at the year's first major, which is a staggering achievement in and of itself.
As the season wears on, look for Federer to bounce back in a big way and dismiss any doubts about him being past his prime at the year's remaining majors—especially in defending his Wimbledon title. Similar concerns surrounded Federer leading up to that event, yet he won his record-tying seventh championship at the All England Club.
Lesson learned. Don't doubt him.