World No. 4, Rory Mcilroy, never challenged for the lead at last week’s grueling PGA Championship at Quail Hollow. The Ulsterman finished well off Justin Thomas’ pace at one over par, tied for 22nd.

Now without a major in his last three PGA Tour seasons, Rory McIlroy ought to be setting his sights on the FedExCup, the winning of which redeemed his 2016 season from total disaster.

Rory McIlroy doesn't know when he'll golf again

Instead, it seems the 28-year-old will be shutting it down for an indefinite period of time. Speaking with reporters after the PGA Championship, McIlroy indicated the rub injury he initially sustained when testing equipment last winter continues to plague him.

“I don’t know what I’m going to do, McIlroy told reporters, saying he could be in action again soon, or he could be out until 2017.

The dependent factor is this: McIlroy’s rib issue is compounded back back spasms and numbness in his left arm, which he revealed for the first time. He indicated he believes a substantial amount of rest if the cure, but is in the process of looking into additional treatment options that could expedite his return to golf this season.

Rory McIlroy aggravated his injury after April wedding

McIlroy also told reporters that he returned to long practice sessions too quickly after a layoff for his marriage to Erica Stoll after the Masters.

“It felt okay through the Masters and I switched it off for a couple of weeks because I was getting married, going on the honeymoon," McIlroy said, indicating he resumed his normal practice reps more quickly than he should have and felt the effects.

It’s been a stop-start season for McIlroy, who switched equipment brands in the off-season. After the South African Open in January, he took six weeks of owing to the rib injury that continues to plague him. He also sat out both the BMW PGA Championship and the Memorial before returning to action at the U.S. Open and missing the cut.

Rory McIlroy was again absent ahead of the British Open, but looked to be in form at Royal Birkdale where he finished tied for fourth. Things had seemed to be trending in a positive direction ahead of the PGA Championship, but it turns out injury issues continue to linger beneath the surface.

The 28-year-old is clearly a man frustrated and tired of playing through injury.

"I want to challenge on a more consistent basis, I need to get 100 percent healthy. I want to get back into that winner’s circle," he told reporters.

McIlroy is currently 43rd in the FedExCup points race. He’d need to be inside the top 30 to qualify for September’s season-ending Tour Championship, which means he’ll have to play in/before the September 14-17 BMW Championship.