Roger Federer admitted he took a little time to get going after dropping the opening set of his first-round match against Wimbledon rookie Lloyd Harris.

Now 37, it is perhaps understandable that the Swiss master is a shade slower out of the traps these days.

But once Federer got into his stride it was only a matter of time before he wrapped up a 3-6 6-1 6-2 6-2 victory.

"I think it's a combination of a few things, my legs weren't moving and things were not happening," said Federer.

"You know, it is always slightly unusual, the first let's say two or three matches here at Wimbledon.

"I couldn't really have any impact. He was doing a good job of returning me. It wasn't like I was serving poorly, you know. I guess I wasn't hitting my spots, and he was reading my serve.

"But I think with my experience I stayed calm. I know I have other things in the bag that I can come up with, other tricks. I just took a bit of time."

Harris has never won a match on grass, but at least he will always be able to say he took the first set he played at Wimbledon on Centre Court, against Federer.

It was only the second time anyone had claimed a set off Federer in a first-round match in his last 17 Wimbledon appearances.

Harris, 22 and ranked 86 in the world, needed a medical time-out after the third set and had his calf heavily strapped.

Playing Federer is hard enough at the best of times, but Harris gamely carried on despite some obvious discomfort.

However, Federer had the finish line in sight as he booked a place in round two and a meeting with Britain's Jay Clarke.

"I don't know him very well," Federer added. "I've seen him around. I know him a little bit better than Lloyd. Not a whole lot, though."