Andy Murray has confessed that he was "very disappointed" with his performance during his 6-0 6-1 defeat to Roger Federer in the ATP World Tour Finals.

Although the Scot acknowledged that he was off the boil at London's O2 Arena, he was quick to admit that his opponent played "exceptionally well".

He told reporters: "It was a tough night. He played exceptionally well. That's for sure. I can say I'm disappointed with my level, but even if I'd played well he probably still would have won.

"He was striking the ball very cleanly and made very few mistakes. I've never lost 6-0 6-0 before, I've hardly ever lost 6-0 6-1. It's very disappointing, it wasn't what I was looking for."

Murray needed to defeat Federer to book a place in the semi-finals after Kei Nishikori defeated David Ferrer in Thursday's earlier match.