John McEnroe has backed Andy Murray to defeat Roger Federer in his semi-final match and win Wimbledon this year.
The 28-year-old has failed to beat the Swiss in their last three matches, but Murray won their last match on Centre Court in the Olympics in 2012 to claim the gold medal.
McEnroe has admitted that he has been impressed with the high level of Federer's play, but feels - at the age of 33 - it will be too much for him to beat Murray to earn the chance to win an eighth Wimbledon title.
"I didn't think Roger was going to win another one. But every time I watch him play like this, you've got to think, 'Well, of course he's got a chance if you're playing this well'.
"But to beat Murray, and in all likelihood Djokovic, to do that back-to-back, best-of-five, that's a tough situation for Roger.
"So that's why I've picked Murray to win the tournament but it's going to be an incredible match."
Murray and Federer face off in their last-four clash later today.