By Abhishek Mehrotra
Federer beat Juan Martin del Potro 3-6 6-7 6-2 6-0 6-3 while Djokovic saved four match points en route to a 6-1 5-7 5-7 7-6 6-1 win over home favourite Jo Wilfried Tsonga.
Here are five thoughts from what was a riveting day at the French Open.
If you see Del Potro playing for the first time...
You'd think he is one of the luckiest players on the tour. The Argentinean caught the tape time after time before seeing the ball land in Federer's half.
But this has nothing, or very little, to do with luck. Del Potro is the flattest hitter of a tennis ball around, with a typical shot clearing net by an inch. You'd think that would compromise on the depth of his shots - Federer himself hits them quite flat at times and consequently doesn't get as much depth as some of the other players - but the 2009 US Open champion's shots seem to skim, almost kissing the net before exploding on or close to the baseline. And he hits them hard. Harder than anyone has in the past two decades.
There were times in the first set when Federer barely had time to finish his service action before the ball was back at his feet, threatening to knock the racket out of his hand with sheer violence. Even against Djokovic or Rafael Nadal, you don't see Fedex scrambling as much as he did on Tuesday. Del Potro unloaded shot after shot, pulling the Swiss from one side of the court to the other before inevitably rifling a winner. And after each point, the 23-year-old would blow on his racket. Comparisons with cowboys and smoking guns are inevitable.
As an aside to this, Federer's doesn't get as much credit as he should for his retrieving abilities. On numerous occasions against Del Potro, he seemed totally out of the point, but somehow managed to get the ball back, relying heavily on the "squash" shot where, with the ball behind him, be brings the racket down almost vertically to generate the spin needed for the ball to cross the net.
The three sides of Federer
Whatever the end result of the match and however he's faring, Federer always conjures up some breathless moments of magic. One such moment came in the eighth game of the second set.
The duo exchanged heavy backhands before a wicked, dipping shot from the former world number one elicited a weak return from Del Potro, giving Federer the chance to run around it to take it on his forehand. The maestro tilted his wrist back, shaping to drop and Del Potro, anticipating it, began to stride towards the net. But instead of bringing the wrist down gently, Federer snapped it while turning the racket head ever so slightly. The end result? A sliced forehand that landed right on the baseline on the deuce side even as Del Potro was looking for a drop on the ad side. Magic.
But that was the unflappable Federer, the one who we're used to seeing. There were some uncharacteristic moments too, with lots of grunts, "Allez!" and "Come on!" thrown in. The most surprising incident came in the second set tie-breaker. Serving 5-4 down, Federer was just about hanging on in the rally when Del Potro whipped another deep, deep forehand - prompting a spectator to shout "Out". It wasn't, and the Swiss netted his return before screaming "Shut up!!" in the general direction of the crowd. A frazzled Federer. A jarring and uncommon sight.
Finally, we saw the ruthless Federer - another rare sighting. Or at least rare in that it's usually not as obvious. With Del Potro struggling to move after the second set [the Argentinean refused to blame the pain in his knee after the loss], the 30-year-old upped the number of slices and drops, making his opponent twist, bend and run - not easy for the 6'6 man when he's at full fitness. With a crocked left knee, it looked excruciating. But this is top level sport. Sympathy can be expressed after you've won.
Don't be fooled by the Djoker
In the match against Tsonga at Court Philippe Chatrier, especially in the fourth set, Djokovic seemed completely out of it. Out of breath, out of stamina and out of ideas. But it's something we've seen before. At the Australian Open earlier this year, the world number one seemed similarly shot, first against Andy Murray in the semis and then again against Nadal in the final. On both occasions, he won.
This time, he had another factor to contend with. The fiercely partisan home crowd. Every point Tsonga won was greeted with roars so loud they could be heard over at Court Suzanne Lenglen, where Federer and Del Potro were battling it out in the other quarter-final. But Djokovic's mental strength has been one of the key improvements in his game over the last 18 months. If his victory over Federer at last year's US Open after being two match points down was special, the win over Tsonga beggared belief. He saved four (!) match points in the fourth set, adopting the same aggression and I'll-go-down-swinging philosophy that saw him best Federer.
It's becoming something of a hallmark for the Serb now. As a fan commented on another tennis forum: "You need to get to match point to beat Djokovic, but if you get to match point, he's going to beat you."
Not completely valid of course, but does have a nice ring to it.
Some sympathy for the losers
It's difficult not to like Del Potro. He's got a great game, is gracious in victory and defeat and is reported to be one of the nicest guys on tour. When he won the US Open as a 20-year-old, it seemed only natural that he would be up there with Federer, Nadal and Djokovic, challenging for all the majors.
But a wrist injury ruled him out for the entire 2010 season, and now, just when he seemed to be cranking up his game back to those dizzy 2009 heights, his knee has started to bother him. For the sake of the game, here's hoping it's nothing serious. We're truly blessed to be living in one of tennis' golden ages, but that shouldn't stop us from being greedy. A fully fit Del Potro would make the game even more interesting.
And what of Tsonga? The Frenchman seems destined to finish his career as one of tennis' nearly men. At Wimbledon last year, he played the match of his life to beat Federer in the quarter-finals, only to run out of steam against an in-form Djokovic in the next round. On Tuesday, with the home crowd behind him and Djokovic nowhere near his best - the Frenchman had another chance to make a title tilt. Instead, he faded away yet again.
Forget the four match points - Djokovic was too good on those. But it is implausible that any of the big three would have faded as spectacularly as Tsonga in the fifth. He's an awesome player, but lacks just that bit of mental strength which separates the good from the great. And at 27-years-old, time is not exactly on his side. One more addition to the list of "Best-player-never-to-have-won-a-Major?" Probably.
When Federer and Djokovic step on to the court on Friday, it'll be a repeat of the 2011 semi-final - one of the best matches of last year. But the circumstances are very different this year. Federer, buoyed by lighter balls and sunny conditions was sublime in his run to the final, while Djokovic was playing the tennis of his life. Neither looks as sharp this time around.
Federer had 43 unforced errors in his win over Del Potro. Djokovic had 34 against Tsonga. Federer has dropped five sets, Djokovic four. At the same stage last year, Federer had yet to drop a set, Djokovic had lost one. Numbers are only one part of the story though.
With the heavier balls and damp conditions in the second week, Federer admitted he hasn't been able to hit through the court - and it has shown in his matches against lower ranked players. The shots are not as deep, nor do they have the penetration that was so obvious last year. Djokovic looks more mortal too - half a step slower and unable to pull of those spectacular shots that had become a regular part of his repertoire last season.
Strange thing to say about a guy who has won a Grand Slam in addition to one win and two runner-up finishes in the ATP 1000 Masters series so far this year, but then such are the standards he set in 2011.
Friday's match will depend on two things. Federer's serve and Djokovic's ability to draw his opponent into long rallies. The Swiss has served poorly so far - his first serve percentage hovered around the 50 mark for most of the Del Potro match [the only exception was the third set - when it touched 65] - and if the pattern continues, he'll find it difficult to keep the points short. And once Federer gets tangled into a baseline slugfest , there is likely to be only one winner.
One thing Federer has done well though, is mix the pace of his shots throughout the tournament, especially off the backhand. He can chip it, slice it, flatten it out or hit it with a lot of topspin. Last year, that shot was crucial in halting the Serb's unbeaten run, and with his forehand misfiring so far, it will become even more important come Friday.
The backhand is a crucial weapon for Djokovic as well - especially his down-the-liner that has the ability to destroy opponents on a good day. Having tried to stay away from Del Potro's forehand on Tuesday, Federer will have to try and avoid the world number one's backhand now. How well he can do that will determine how far he can push Djokovic.
Thanks to the luck of the draw and some gritty tennis, we've been granted another chance to witness two modern greats play each other yet again at the French Open. Let's hope it's as explosive as last year's encounter was.