British number one Andy Murray has revealed that he treated today's ATP World Tour Finals opener against Tomas Berdych like a Grand Slam contest.
The Scotsman managed to come from a set down to defeat the 27-year-old and claim his first win in the Round Robin stage.
"It's obviously very tough from the start," Murray told Sky Sports News. "Tomas has had a great year. I've played him a few times this year and every time it's been very tough. It was the same again today.
"You need to, if you can, treat it like a knockout. If you win your first two matches you've got a good chance of progressing, so you just need to focus like it's the end of a major event."
Novak Djokovic will come up against Jo-Wilfried Tsonga at the O2 Arena in London this evening.
