John McEnroe was surprised when Andy Murray named Ivan Lendl as his new coach but thinks his old rival may prove to be the missing ingredient the Briton needs to take his career to the next level.
World No 4 Murray has been runner-up in three Grand Slam finals, including at the last two Australian Opens, but has been blown away in them all, continuing his country's long wait for a men's champion in the sport's four major tournaments.
"I hate to give credit to Lendl but (Murray) needed to do something out of the ordinary instead of going with the predictable re-tread," McEnroe told reporters in Adelaide on Monday.
"This is definitely something that was, to me, unexpected. I didn't know that Lendl wanted to coach. He could bring something to the table, without a doubt.
"Lendl didn't win a major until he was 24 and guess what? Murray is 24 right now.
"So that could provide something worth it for Murray, I'm going to be paying attention to that, see how it works out."
McEnroe, who won seven Grand Slam singles titles, had a fierce and unfriendly playing rivalry with Lendl, who he once described as a "scary robot".
Game, set, match: high-profile tennis partnerships
Brisbane International: Murray crushes lame Dolgopolov
Akram flays Team India for negative body language
While Sachin keeps fans waiting, Federer achieves century
Roger Federer joins an 'exclusive' club