Rafael Nadal: Will This Be His Best Chance to Win the Year-End Championships?

While Roger Federer was winning Paris, and Novak Djokovic and Andy Murray were falling there before the semifinals, one man was sitting back and watching it all: world No. 2 Rafael Nadal.

Recovering from injury, Nadal is poised to make his return to the court at the ATP World Tour Finals in London, kicking off this Sunday.

Nadal has never won the season-ending event, a notable blank on his ledger as he's won all of the other titles that make a player legendary—all four Grand Slams, the Davis Cup and an Olympic gold medal—joining Andre Agassi as the only other male in history to pull that off.

Now, though, with questions arising about the player in front (Djokovic) and the one behind (Murray) him in the rankings, could this be Nadal's time to be crowned best of the best?

He's made one career year-end final and it came last season when he fell to Federer. His longtime Swiss rival is playing at an extremely high level, having won 12 matches in a row that included titles at the Swiss Indoors in Basel and the Paris event.

As of right now, Federer appears to be the favorite heading into the Tour Finals, an event he's won five times.

However, there is that matter of him having an 8-17 head-to-head record against the Spaniard. Federer does turn that around, though, when the two play on faster surfaces.

This time around, Nadal's extended layoff could have some benefits going into the finals, much like Federer's recent one has had on his indoor success the past couple of weeks.

As for matching up against Djokovic, things could get tricky for Nadal—Djokovic has beaten him six straight times, and all of those matches were finals. But Djokovic seems to have hit a bit of a rough patch recently due to injury.

Murray, who beat Nadal in the finals of the Japan Open a few weeks ago, could present a different challenge.

He's at his best on faster surfaces, but Nadal has defeated him under those conditions, most notably at Wimbledon and the U.S. Open this year on the way to a 13-5 career record against him.

While 2011 might not have been up to Nadal's usual standards with only three titles won, the World Tour Finals could be the perfect opportunity to erase some of those tough losses—provided he's healthy.