John McEnroe tells the Independent that while he thinks old rival Ivan Lendl's decision to coach Andy Murray was a good one, it's too early to tell whether it will reap benefits for the world No. 4.
"Actually this is the first time you can get some kind of gauge of how it's going," he said. "It was too early in Australia. At first I thought it was crazy, then I thought it was going to work out. Now we'll have to wait and see. You have to give it some time."
McEnroe added that Murray needs to be focused on his tennis rather than be distracted by physical problems.
"I just remember watching Federer the first year he won Wimbledon," said McEnroe. "He was struggling with his back problem. I remember it vividly. It looked like there was a chance he was not going to finish. He had that look in his eye. Then somehow he found the wherewithal to dig a little deeper, and suddenly he wins the thing and he's a different player."