Will Henrik Stenson’s knee, Rory McIlroy’s putting doom Euro Ryder Cup bid?

Henrik Stenson’s nagging knee injury and Rory McIlroy’s lingering putting woes may keep European Ryder Cup captain Darren Clarke up nights worrying about his team’s leading men.

Reigning British Open champion and 2013 FedEx Cup winner Stenson withdrew from Thursday’s first round of The Barclays due to pain in his surgically repaired knee during an opening 3-over 74.

“My right knee, which required surgery in December, 2015, has flared up again,” Stenson said in a statement. “Regrettably, I need to withdraw this week to allow time for an MRI and see what the next step is.”

The Ryder Cup is just five weeks away, and with Stenson (three bogeys, one double and a triple on Thursday), a roster full of rookies and McIlroy’s new flat stick behaving much like the old one, Clarke will no doubt be rather interested in the result of Stenson’s medical test.

Of course, Stenson withdrew from the U.S. Open with injuries and went on to earn his first major title a month later at Royal Troon and an Olympic silver medal in Rio two weeks ago. So Clarke can hold on to the hope that the world No. 4 will rise again from his sick bed and play a starring role at Hazeltine in September.

As for McIlroy, the change from his Nike Method blade to a Scotty Cameron mallet-type club to start the first of four FedEx Cup playoff events did nothing to help his putting, which was largely to blame for his missed cut at the PGA Championship three weeks ago.

The four-time major victor is 96th in SG: putting on the PGA Tour, where he is winless in 2016. On Thursday, he needed 31 putts, which included four misses from within eight feet.

McIlroy was fortunate, with an opening 71 at Bethpage Black, to be just five shots back of 18-hole leader, and U.S. Ryder Cup hopeful, Patrick Reed.

“Tee to green, the rust wasn’t really there but on the greens,” McIlroy said, “I felt a little tentative at the start.”

He was even more fortunate, when his ball wiggled a tad on the fourth green, to avoid the type of penalty that Dustin Johnson incurred at Oakmont. Cleared of any wrongdoing by a rules official, McIlroy posted one of his three birdies on the par-5.

“I addressed my ball, sort of put my putter behind it, but with the wind, that’s a very exposed green. And with these poa greens as well, sort of what happened with Dustin at the U.S. Open as well, a tiny bit of movement, whether it’s wind or even pressure of your feet,” he said.

“I told the ref what happened, and he said, ‘Look, with the wind and everything, I don’t think you caused the ball to move,’” McIlroy noted. “I just played it from where it was.”