World number six Gael Monfils has been forced to pull out of the ATP World Tour Finals due to a rib injury.
The 30-year-old, who has already played two of his three round-robin ties, will now be replaced by David Goffin.
Monfils managed to battle through the final two sets of his meeting with Dominic Thiem on Tuesday, but he can play no further part in the tournament at the O2 Arena in London.
Goffin will now face Novak Djokovic in Thursday's final group fixture, with Monfils's hopes of progression already over following a loss in three sets to Thiem and a straight-sets defeat to Milos Raonic earlier this week.
"I can't play for tomorrow because I still feel worse and worse - my ribs, that I had lately," he is quoted as saying by Sky Sports News. "Yesterday was tough in the game. Today I couldn't be feeling great and couldn't practise, so I just decide that I couldn't play tomorrow.
"You work so hard for this moment, then not be able play your best - it is a huge disappointment for me. I attempted to play in two matches and I have a couple of stuff I wanted to show. I'm disappointed, but, as I say, it will give me more strength for next year."
Monfils picked up the injury during the Stockholm Open last month and has since been unable to fully shake it off heading into this end-of-season tournament.
