Watch List: Juan Martin del Potro back as World Tour Finals spots up for grabs

Juan Martin del Potro intends to play out the rest of the season if his wrist holds up. (Eduardo Di Baia/AP)

The spotlight this week is on the ATP's Race to London. Juan Martin del Potro, who is seventh in the standings for the World Tour Finals, is back after spending the last month rehabilitating the left wrist that forced him to retire from Davis Cup. Tomas Berdych, Jo-Wilfried Tsonga and Janko Tipsarevic are all in the running for the last four spots at the eight-player, season-ending event and they're all in action as the tour returns to Europe.

The real race is between Tsonga and Tipsarevic. The Frenchman is in the eighth qualifying spot with a 485-point lead on Tipsarevic. With 250 points up for grabs this week, Tipsarevic could make up some ground before the Paris Masters.

Stockholm: The premier tournament for the men this week is the philosophically named If Stockholm Open, where Tsonga and Berdych top the draw. Berdych defeated Tsonga in the quarterfinals at the Shanghai Masters. That sums up his year nicely, as the Czech seems to have replaced Tsonga and Del Potro as the guy who's most likely to break the top-four stranglehold, especially on hard courts. Tsonga has played a lot of tennis over the last few weeks, winning Metz, making the final of Beijing and reaching the quarterfinals of Shanghai. Does he have enough in the tank to keep pushing toward London?

Vienna: Welcome back, Delpo. The Argentine has been training hard at home and intends to play out the rest of the season if his wrist holds up. He's the top seed here, with Tipsarevic, Tommy Haas and Jurgen Melzer rounding out the top four seeds.

Moscow: It's the last week of the WTA's regular season, which means the top eight women who have qualified for the WTA Championships are making their way to Istanbul, leaving this week's fields a bit light. Samantha Stosur continues her nonstop post-U.S. Open play to lead the field in Moscow, along with Marion Bartoli, Caroline Wozniacki and Ana Ivanovic. It's been a curious schedule for Stosur, who's playing her fourth tournament in four weeks. It was all part of a late-season push to qualify for the WTA Championships, but that chance ended with an early loss in Beijing. She and Bartoli will still head to the Championships as alternates.

While the women boast two Grand Slam champions in their draw, it's a journeyman's special for the men. No. 20 Alexander Dolgopolov leads the field.

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