Andy Murray will face Novak Djokovic with the ATP World Tour Finals title and year-end number one ranking at stake on Sunday, November 20th 2016.
The 35th meeting between the pair will also be the first time the season finale has ended with the number one spot on the line.
Murray replaced Djokovic as number one earlier this month, and the Briton is on a 23-match winning streak.
“I’m really privileged to be a part of history on Sunday,” said the Serb.
Djokovic has won the last four titles in London and will overtake Murray with another win.
He added: “We’ve known each other for so many years. This is maybe one of the biggest matches we will ever play, so let’s enjoy it.”
Murray said: “Sunday is the last day for a while, we get a break after that. I’ll just give my best of what I’ve got. Hopefully it’s enough.”
Saturday’s semi-final win over Milos Raonic brought Murray his best ever winning run of 23 matches, but it also came at a cost.
At a gruelling three hours and 38 minutes it set a tournament record, and came just four days after Murray spent three hours and 20 minutes on court with Kei Nishikori.
The Scot, 29, has spent a total of nine hours and 54 minutes on court during his four matches this week, compared to six hours and 31 minutes for Djokovic.
“I don’t know how I’ll feel on Sunday,” said Murray, who headed to a nearby hotel rather than his Surrey home after the win over Raonic.
“The physical side, obviously the body is a bit sore after such a long match, but mentally it was tiring too.”
Murray will at least hope to enjoy the same rapturous reception each time he has stepped on court this week, with crowds of 17,000 eager to salute the new number one.
“When you’re out there competing, the atmosphere helps for sure,” he said.
“Playing in front of a pretty packed crowd at this stage of the year definitely gives you an extra boost, helps you to keep pushing right to the end.”