ATP World Tour Finals 2013 Format: Rules, Players and Schedule

The tennis season will conclude this week with the year-end championships in London, better known as the ATP World Tour Finals.

World No. 1 Rafael Nadal headlines the list of competitors, which includes defending champion Novak Djokovic and six-time winner Roger Federer.

After missing the second half of the 2012 season because of a knee injury, Nadal is back with a vengeance and ready to take aim at his first-ever year-end championship. The Spanish superstar is not alone, though. David Ferrer, Juan Martin del Potro, Tomas Berdych, Stanislas Wawrinka and Richard Gasquet will also be gunning for a career-defining triumph this fall.

Here we'll get you set with everything you need to know for this week's season finale in London.  

*Information courtesy of BarclaysATPWorldTourFinals.com.  

Where: O2 Arena, London

When: Monday, Nov. 4 through Monday, Nov. 11

Watch: ESPN2, Tennis Channel

Live Stream: ESPN3

Schedule: Click here for updated tournament schedule 

Singles Format

The eight qualifying players will be split up into two groups of four. The players will take on each of the other three competitors in their group with the top two finishers in each group advancing to the single-elimination semifinals. 

Like all other non-major ATP tournaments, each match will be three sets maximum with a tiebreak in each set, including the third if need be.

The semifinal qualifiers will be determined by greatest number of wins, followed by greatest number of matches played. The head-to-head result will determine which player advances if there is still a tie at that point. 

The Players

Group A

Rafael Nadal

The current world No. 1, Rafael Nadal has had a tremendous 2013 season since returning from a seven-month layoff, but has fallen off some since his 26-0 start to the summer hard-court season. 

Nadal has dropped three of his last nine matches coming into London.

David Ferrer

If there's a dark horse capable of surprising tennis' elite this week, it's David Ferrer. The third-ranked Spaniard has reached the final of each of his past three tournaments, and upset Nadal in the semifinals at the Paris Masters this past weekend. 

Ferrer isn't a physical specimen at 5'9", but his never-say-die style can't be counted out. 

Tomas Berdych

While top-ranked Czech Tomas Berdych is a dangerous player, he's yet to win a single title in 2013, which should serve as a major red flag. The 28-year-old has had some strong showings in Thailand and Beijing recently, but hasn't displayed the form required to beat out the world's best in London.

Stanislas Wawrinka

Stanislas Wawrinka will make his first career appearance at the ATP World Tour Finals this November. The Swiss star has certainly earned the right to play for the year-end title. He reached the semifinals at the U.S. Open earlier this year, earning his best-ever finish at a major.

Group B

Novak Djokovic

Defending champion Novak Djokovic will be as dangerous as ever. Although he's had his No. 1 ranking stripped from him, he's playing phenomenal tennis and is still by far the best returner in the men's game.

Juan Martin del Potro

Juan Martin del Potro has had a spectacular year. Although he wasn't able to capture a second Grand Slam title, he made a memorable run to the semifinals at Wimbledon and has picked up four singles titles in 2013. Look for the world No. 5 to advance from the group stage in London. 

Roger Federer

Roger Federer will be a fan favorite in London, for obvious reason. Federer has won this event six times since 2003, twice in the English capital. However, he enters this year's finale with just 40 match wins and one singles title to his name.

Richard Gasquet 

For the first time since 2007, Richard Gasquet will compete for the year-end title. The veteran Frenchman qualified thanks to Andy Murray's withdrawal following back surgery. Though it sounds harsh, don't anticipate the world No. 9 to make it past the group stage this week.

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