Roger's first-serve needs to be firing on all cylinders
Coincidentally, this is the third time in a row that these two are meeting each other in a Grand Slam semi-final, with victories for Djokovic in their previous two encounters at the 2010 US Open and the 2011 Australian Open.
So the question going into the blockbuster semi-final is whether this third meeting in a row will be a charm for Roger Federer, or will Novak Djokovic continue his dominance over the lesser mortals on the ATP Tour this season?
So, let's take a look at how the rejuvenated Roger Federer matches up with the seemingly unbeatable Novak Djokovic.
Even Grand Slams aren't Mr. Roger's Neighborhood anymore
This meeting at Roland Garros will be the first time in his career that Roger Federer won't be starting out as favorite against Novak Djokovic in a Grand Slam encounter.
While Roger Federer was expected to win at the US Open last year and the Australian Open this year, the Parisian clay sees a 43-match unbeaten Novak Djokovic start out as an established favorite.
With Federer expected to lose this encounter, as per the seedings and the form, would it give the 2009 French Open winner some sort of mental relaxation? Or would Novak Djokovic's recent stranglehold on the Swiss maestro play on Federer's mind?
It seems this revitalized Roland Garros version of Roger is coping with the underdog tag quite well so far, comfortably blowing through his quarter of the draw.
However, in Novak Djokovic he comes up against a totally different, and well-rested, proposition.
First Serve Percentage will be the Key for Roger Federer
When Federer played Monfils in the quarterfinal, his first-serve percentage was an unimpressive 53 percent.
Against possibly the best serve-returner since Andre Agassi, i.e. Djokovic, this could potentially be one of the major reasons for his downfall.
If Federer is unable to put over 65 percent of his first serves in play, he is most likely to be left chasing the game. The dismal serving performance in the quarterfinal saw Monfils break Federer three times, and you can rest assured Djokovic would be manhandling Roger with such a first-serve performance.
Who will win this third consecutive Grand Slam semi-final between the two?
So first serves are key for Federer, as he ended up winning 77 percent of the points when he did get those first serves into play against Monfils.
Shorten the Points and Go for the Winners (Well, Duh!)
Against a powerful baseline rallying machine like Djokovic, Federer would need to shorten the points and go for the kill each time he sees an inkling of an opportunity.
He needs to trust his instincts and lay into those sizzling forehands, and have enough confidence in his one-handed backhand to attempt ending the points early.
Against Monfils, Roger had 41 winners, of which only four were aces. However, the downside to such a strategy is mounting unforced errors, which were 42 for Federer against Monfils. It served him well that Monfils made 53 of his own unforced errors, but yet again Djokovic isn't likely to offer similar sweets on a platter.
Roger Federer will need to believe in his own passing shots in order to beat Novak Djokovic, otherwise Djokovic will take away the mental edge right from the start.
Therefore, in short, Roger Federer needs to have one of those 'perfect games' of his after a long, long time against either Nadal or Djokovic.
Despite his Best Efforts, Roger Expected to Fall Short: Djokovic in Four
Unfortunately, it seems likely that this would be the end of the road for Federer as far as Roland Garros 2011 is concerned. He would be expected to take at least one set off the world No. 2, though.
Novak Djokovic seems primed for his first final appearance at the French Open, thus enabling him to match John McEnroe's 42-match season-opening unbeaten run, and also Ivan Lendl's 44-match unbeaten run overall.