Watch List: WTA Championships, Roger Federer at home event highlight week

The eight qualifiers for the WTA Championships pose with the trophy. (Matthew Stockman/Getty Images) The Watch List spotlights the must-know storylines for

The eight qualifiers for the WTA Championships pose with the trophy. (Matthew Stockman/Getty Images)

The Watch List spotlights the must-know storylines for the upcoming week in tennis. This week, Serena Williams hopes to end her remarkable season on a winning note at the WTA Championships in Istanbul, while the Roger Federer returns home to the Swiss Indoors.

WTA Championships

The women's elite finish their season this week, as Istanbul hosts the WTA Championships for the last time before the exclusive eight-player event moves to Singapore next year. It's been a strong run for the host city, which has been able to draw near-capacity crowds for almost every session, including more than 16,000 for last year's final between Serena Williams and Maria Sharapova.

Williams is looking to defend her title and further consolidate her position at the top. With 10 titles this season, winning the Championships would be the cherry on top of Serena's career year.

Sunday night's draw ceremony placed the eight players into their respective groups. Williams and No. 2 Victoria Azarenka are the top seeds in each group:

• Red Group: Serena Williams, Petra Kvitova, Agnieszka Radwanska and Angelique Kerber.
• White Group: Victoria Azarenka, Li Na, Sara Errani and Jelena Jankovic.

Serena's Red Group is the tougher of the two considering how well Kvitova, Radwanska and Kerber are playing. The most tantalizing match is Williams vs. Kvitova. In February, Williams beat Kvitova 3-6, 6-3, 7-5 in a high-quality match in Doha to reclaim the No. 1 ranking. Kvitova is 0-4 against Wiliams, but their last three matches have turned on a handful of points. Radwanska will try to play the spoiler. She's a combined 1-11 against the powerful Williams and Kvitova, with her lone win coming against an ill Kvitova here last year.

In the White Group, Azarenka is coming off a disappointing Asian swing, while Li and Jankovic enjoyed a confidence-boosting fall. Azarenka does have winning records over the three women in her group. She took some time off to recharge after losing early at the China Open, spending some time in Switzerland and Australia to visit her boyfriend, Redfoo, who is Down Under judging The X Factor. Look for Azarenka and Li to come out of this group, though a relaxed and motivated Jankovic is more than capable of spoiling the party.

Group play begins on Tuesday.

Swiss Indoors

[Complete draw]

Defending champion Juan Martin del Potro leads the field, which includes Tomas Berdych, Roger Federer and Stanislas Wawrinka. One player noticeably missing: Rafael Nadal, who withdrew last week because of fatigue.

Third-seeded Federer, playing in front of his hometown crowd in Basel, Switzerland, has been drawn into Berdych's half and will open against Adrian Mannarino. Berdych, Federer, Wawrinka and Richard Gasquet are still fighting to qualify for the ATP World Tour Finals, and the results from the projected semifinals of Del Potro vs. Wawrinka and Federer vs. Berdych will set the table for next week's Paris Indoors, the final regular-season event.

Valencia Open

[Complete draw]