Sports-lovers staying in luxury London hotels may be interested in catching top tennis pros compete at the Barclays ATP World Tour Finals, taking place at The O2 until November 27th.
Some of the world's best players have come to London for the event, which puts the top eight in the men's competition against each other in a gruelling end-of-season series.
Only the best eight singles and eight doubles teams of the season qualify to take part in this event, including big names Rafael Nadal, Novak Djokovic, Andy Murray and Roger Federer.
This is the third year that the event has returned to The O2, with Federer beating Nadal to claim the final's title in 2010 for the fifth time.
Additionally, the event looks to raise money for good causes, with this year's stars netting over £400,000 for Great Ormond Street Hospital.
The top players attended the event's exclusive opening gala, with the proceeds going towards the world-famous children's hospital.
"I'm very happy to be here tonight, and I'm proud to qualify for the season-ending event for a 10th time," said defending champion Federer.
"We have a great group of players this year and it's fantastic to have this launch party. It's something new and it's for a great cause. It's very nice to see that the ATP and the players have come together to support charity tonight."
An auction was held on the night, with the singles and doubles players collectively purchasing a vital piece of equipment for the hospital with a value of nearly £19,000.