If you thought Rory McIlroy might be flagging just a little, following a run of terrific form interrupted only by his regular vociferous defences of the PGA Tour in the face of the LIV Golf threat, well … you’d be right.

He’s under the weather, he’s tired after a punishing US Open and he’s looking forward to his time off starting Monday, when he’ll start his preparation for the Open Championship at St Andrews. We could be forgiven for thinking that he might not set the world on fire in his last stop before the big rest at the Travelers Championship.

Guess what? He set the world on fire.

With a scintillating 62 at TPC River Highlands, McIlroy seized a share of the opening-round lead with the lowest Day 1 score he’s ever shot in a PGA Tour event. And he did it with very little preparation.

“I didn’t hit any golf balls Monday and Tuesday,” he said. “I flew back down to Florida for a day, spent the night in my own bed, flew back up Tuesday, didn’t come to the course, and then yesterday playing the pro-am in the rain wasn’t really great preparation, but … I played well at Brookline. I’m not going to lose it in two days. I knew my game was good.”

It started out just modestly good, with an opening nine that felt “slow, in a way,” at least to McIlroy. His first birdie came at the 13th, his fourth hole of the day, when he buried a 31-foot birdie putt on the par 5. He followed with another birdie on 15, and finished off his opening with an approach to nine feet on 18 that he converted for a third birdie. It was at that point that he truly did the “caught fire” thing, making five more birdies on the front to post a 30. The most impressive of the bunch may have been this bomb from 47 feet on 7:

He finished his round with a 332-yard drive on the short par-4 ninth, and a simple 44-yard pitch nestled inside two feet, setting up his eighth and final birdie in a round with no bogeys. Coming off Brookline, the performance felt like a breath of fresh air.

“It’s like the anti-US Open here,” he said. “It’s like US Open rehab coming here. You’re like, oh, I can actually make some birdies. This is nice.

McIlroy also continued what has started to seem like his second full-time job: backing up the PGA Tour. When asked for comments on Jay Monahan’s press conference and the new PGA Tour schedule, he seemed sincerely pleased.

“Some of the things that he said yesterday I think are great,” he said. “Some of the changes that were made to the schedule, to … I think Webb [Simpson] was talking about it, it’ll make the regular season much more competitive. Everyone starts at zero at the start of the year. Everyone has the same opportunity to make the big events with the big prize funds and whatever. I think it’ll make it more competitive and make it a more compelling product, honestly. I think it’ll be good.”