Lucky fans scored an autograph from Novak Djokovic at The O2 in London; Getty Images
Novak Djokovic v Milos Raonic and Dominic Thiem v Gael Monfils were both thrilling matches that fans lapped up in London. Here are the best pics of the action on Tuesday.
Jamie Murray and Bruno Soares (R) were too strong for the Bryans in the first match of the day in London on Tuesday; Getty Images
Dominic Thiem arrives at The O2; Getty Images
Dominic Thiem serves at The O2; Getty Images
With his loss to Thiem, Gael Monfils (pictured) cannot advance to the semifinals at the ATP Finals; Getty Images
Dominic Thiem (L) beat Gael Monfils (R) to keep his semifinal hopes alive in London; Getty Images
Treat Huey (R) and Max Mirnyi fell to 0-2 in their round-robin group; Getty Images
Ivan Dodig (L) and Marcelo Melo defeated Huey/Mirnyi in straight sets; Getty Images
Milos Raonic (pictured) fell to 0-8 lifetime against Novak Djokovic; Getty Images
Novak Djokovic in action at The O2 in London; Getty Images
Novak Djokovic (L) and Milos Raonic played out a thrilling round-robin match that went to two tense tiebreaks; Getty Images
Novak Djokovic (R) is interviewed by Annabel Croft after sealing a spot in the ATP Finals semifinals; Getty Images
Lucky fans scored an autograph from Novak Djokovic at The O2 in London; Getty Images