The World Tour Finals seedings are set and the eight best tennis players in the world are turning their attention toward London for the year-end championship. It may not garner quite the publicity of any Grand Slam event, but the O2 finale is always a special time filled with exceptional tennis.

And at this year’s event, one question in particular will make the action particularly fascinating: can Roger Federer end the year with a title?

In a literal sense, this question certainly doesn’t need to be asked. Of course Federer can win; he’s the third-ranked player in the world and is wrapping up a sensational season in which he single-handedly altered our notions about aging in tennis. You’d be hard-pressed to find a tennis fan who doesn’t believe he’s still the second-best player in the world, even at age 34.

Nevertheless, Novak Djokovic–at the top of his game and six…