Rory McIlroy weathered drenching rain and gusting winds to fire a five-under par 66 and seize a share of the clubhouse lead at the Genesis Invitational, where Aaron Rai was six-under through 16 holes when darkness halted play.

Northern Ireland star McIlroy, who completed his career Grand Slam with a Masters triumph last year, had six birdies and a bogey and was joined in the clubhouse on five-under by American Jacob Bridgeman.

Both came back strong from a rain delay of almost three hours, the soaking showers giving way to gusting winds in the afternoon.

World number one Scottie Scheffler was among the late starters who struggled. He was unable to find a birdie to balance a double-bogey and three bogeys that left him five-over through 10 holes and sharing last place when darkness fell.

Meanwhile England’s Rai was rolling. Three-under through 12 holes, he birdied 13, 15 and 16 to surge to the top of the leaderboard, where he’ll hope to stay when the round resumes on Friday.

While Scheffler’s tee time was delayed, McIlroy started on time and was two-under through three holes.

He came back from the delay to roll in a 30-foot birdie putt at the fourth, then added a 19-foot birdie at the eighth and a birdie at the par-five 11th.

A bogey at 16 briefly dropped him out of the lead, but McIlroy responded with a birdie at the par-five 17th.

“I’ve definitely got more comfortable playing in conditions like this over the past few years as I’ve gotten more comfortable in controlling my ball flight,” McIlroy said. “I’ve started to just really enjoy this style of golf.

“Honestly, I haven’t always had the skill set to excel in (the conditions),” he said. “To start to enjoy them and have the shots to succeed on days like this, that’s a really satisfying thing to be able to be, you know, nearly 20 years into a career and still feel like you’re getting better at some aspects of the game.”

‘Pretty tricky’

McIlroy said playing in the rain posed little problem. Play was halted as water pooled on the already soaked Riviera Country Club course — the classic layout in Pacific Palisades where he has come up empty in eight prior starts.

Instead, he said, it was the afternoon winds that made it “pretty tricky.”

Bridgeman, a 26-year-old American chasing his first PGA Tour title, said the same, but he reveled in the challenge.

“It was great,” he said. “The rain was tough. The wind might have been a little bit harder than the rain, but it was cool.”

He got off to a jerky start, with an eagle at the first followed by a double bogey at the fourth.

But he picked up steam after the delay with five birdies, his four-footer at the par-five 17th putting him atop the leaderboard.

“I think one of my strengths is kind of flighting shots down, hitting shots where people don’t really know how far it’s playing, what the number actually is and just kind of feeling it out ... I think today especially in the wind it played into my favor,” Bridgeman said.