Andy Murray has described his ATP World Tour Finals semi-final showdown with Milos Raonic as "one of the hardest matches" he has ever played.
The world number one went the distance against the Canadian, requiring tie-breaks to win his two sets in a match that clocked in at three hours 38 minutes, a tournament-record length.
"I played some great points and managed to get the break at the end," Murray told BBC Sport afterwards.
"It was an amazing atmosphere. The longer the match went on the louder the crowd got. This is what we play for. Matches like this and arenas like this. This is one of the hardest matches I've played indoors.
"I didn't expect to play a long one with someone with a serve like Milos. I'm tired. I've played so much tennis over the last few months. I'll give it my best effort [in the final] - the best of what I have."
The Scot will face either Kei Nishikori or Novak Djokovic in tomorrow's final at London's O2 Arena.
