Jason Day has a shot at a 59 at BMW Championship

Thursday’s storm delay sent Jason Day into the Conway Farms locker room, where his fellow competitors and chums tried out their best material.

Among their questions, according to Day: “Are you playing off the ladies’ tees?” “Are you playing a different golf course?” “Is every drive downwind for you?”

It’s all flattering, of course. In an event that features the best of the best — the top 70 on the FedEx Cup points list — Day has elevated himself into a category of his own.

He is 10 under par at the BMW Championship, and his first round is not complete after the horn blew Thursday afternoon.

It will resume Friday with a cliffhanger: After bombing his drive 346 yards on No. 9, Day has a 44-yard pitch from the right rough. If he holes it, he’ll become the seventh man to shoot a 59 on the PGA Tour.

The last was Jim Furyk, who did it two years ago in this event at Conway Farms. Furyk’s round was considered one-in-a-million because no one else shot better than 65 on the day.

The best completed score Thursday was a six-under 65 by Daniel Berger, a 22-year-old PGA Tour rookie. He finished his round by holing out from 67 yards on the ninth hole, but from the left rough. So Day joked that they are “totally different shots.”

Matt Kuchar shot a 67 and was stunned by Day’s score.

“It’s amazing what he has done,” Kuchar said. “It was blowing a constant 20 miles an hour all day.”

Day played with Jordan Spieth, who got overshadowed despite making a hole in one and playing the other 16 holes he finished in three under.

Spieth’s magical moment came on the 186-yard second. He struck a seven-iron and called out: “Be enough. Go! Go!” Good call. The ball landed shy of the green and bounced up before rolling in.

Day also made an eagle, holing out from a fairway bunker from 79 yards on No. 1.

“It landed perfect,” Day said. “Once it bounced up and started spinning, I knew it was going to go in.”

Day entered the BMW having won three of his last five tournaments — the Canadian Open, the PGA Championship and the Barclays, in which he closed 63-62.

His massive drives Thursday included a 361-yard high draw on No. 3 that he followed with a pitch to five feet for birdie.

His final drive of 346 yards was 23 yards longer than anyone else in the field on No. 9. As they walked up the fairway, Spieth told him he needed to hole his pitch for 59.

Day was confused, thinking Conway Farms was playing to a par of 72, not 71.

“I’m trying not to attach myself to a number,” he said. “Then I start thinking about the outcome, instead of just trying to rip my driver as far as possible down the fairway.”

tgreenstein@chicagotribune.com