Rory McIlroy recovered sufficiently from a back injury to begin his defence of the Players Championship but he ended round one seven shots off the pace.

The world number two only arrived at TPC Sawgrass on the eve of the PGA Tour’s flagship tournament, having opted to stay at home for treatment on the injury that forced him to pull out of last week’s Arnold Palmer Invitational at Bay Hill.

He showed no obvious signs of discomfort in crushing his opening drive 329 yards down the middle of the fairway, but he took 73 more shots for a two-over par total, with birdie putts on the 16th and 17th holes grazing the edge of the cup.

“It was fine,” he said when asked how his back felt during the round.

“The most discomfort was when the ball was below my feet or with chipping.

“But it’s weird. I played on Friday; it’s not as if I’ve taken a ton of time off, I just felt unbelievably rusty out there.”

McIlroy’s Ryder Cup team-mate Sepp Straka is alongside three Americans setting the clubhouse pace on five under.

Austrian Straka chipped in for an eagle three on the par-five 16th in his bogey-free 67 to join Maverick McNealy, Lee Hodges and Sahith Theegala atop the leaderboard.

“We were fortunate to play in the afternoon with hardly any wind and the greens a lot softer,” said Straka, referring to the heavy rain that doused the course earlier in the day.

England’s Tommy Fleetwood was among those playing in the worst of the weather. He briefly reached five under, after what he called a “complete bonus” run of eagle-birdie-birdie on Sawgrass’ notoriously difficult 16th, 17th and 18th holes.

Having started on the 10th, the world number three then birdied the second but a torrential downpour that halted play for around 25 minutes checked his momentum, and successive bogeys on the fourth and fifth holes dropped him back into the pack.

He is in good company on three under, with Sweden’s Ludvig Aberg, Norwegian Viktor Hovland and American Xander Schauffele also enjoying solid starts.

The rain delay meant four players were unable to finish their opening rounds as the sun set and darkness fell.

Among them is unheralded American Austin Smotherman, who will return at 08:50 local time on Friday to face a 15-foot birdie putt on the ninth hole – his 18th – to take the first-round lead.

In rapidly fading light, Smotherman hit his third shot on the par-five hole into the heart of the green, but while his playing partners opted to finish the hole, he decided to mark his ball and wait for the morning light and fresher greens.