US Open: Why Phil Mickelson will play 36 holes Friday while Andrew Landry will hit one putt

OAKMONT, Pa. — The 2016 U.S. Open is a mess, mostly because of stop-and-go rain Thursday that threw the schedule into chaos, but partly because of how the USGA has responded to said chaos.

Consider this: At 7:30 a.m. ET Friday morning, when Round 1 play resumed, tournament leader Andrew Landry lined up a 10-foot putt on his final hole, drained it, then went home for the day.

Two hours later, Phil Mickelson, who didn't play at all on Thursday, teed off to start his U.S. Open. If his round takes about 4½ hours to complete, that puts him in the clubhouse at around 2 p.m., giving him about two hours to regroup before he heads back out to the course for another 18 holes.

So, Phil Mickeslon is going to play 36 holes Friday, while Andrew Landry will hit one putt.

And it's going to be like that for the entire field.

Tee times for the first two rounds are set up in waves – there's a morning wave and an afternoon wave, with waves flip-flopping between Rounds 1 and 2. So if you played in the morning wave on Thursday, you'll play in the afternoon wave on Friday, and vice versa.

This is done in the interest of fairness, even if it doesn't always work out that way.

But when rain blasted Oakmont Country Club on Thursday, that all changed. Only nine players actually completed their rounds before play was halted at 3:51 p.m. Another 78 – or fully half the field – hadn't even started their rounds.

Friday morning began with Thursday's first wave (let's call them Group A) completing their rounds, with the second wave (Group B) beginning sometime after 8 a.m.

Got that?

The USGA has opted to keep the flip-flopped schedule, which originally called for Group A (which includes Landry, Jordan Spieth and Rory McIlroy) to tee off beginning at 7:15 p.m. Friday. That plan has been scrapped. Instead, Group A will tee off Saturday morning, leaving Group B (which includes Mickelson, Jason Day and Dustin Johnson) to play 36 on Friday.

"Thirty-six holes around this place with the heavy grind and stuff, it's going to be quite tiring for the guys, but they're getting a golf course that's very soft," said McIlroy, who was 7-over in his first round and already in danger of missing the cut. "Even though they haven't seen the golf course like this either, they'll get a good feel for it and be able to get back out there straight away again today."

Fairness will kick back in on Saturday, when Group A (at least those who make the cut) will play 36 as Round 3 begins.

The USGA's expectation is the tournament will be back on schedule come Sunday.