FARMINGDALE, N.Y. — What felt like a battle for Brooks Koepka looked like a runaway Friday in the PGA Championship.

Koepka backed up his record-tying 63 with a round that put him in a league of his own. With three birdies in a four-hole stretch at the start and at the end, the defending champion posted a 5-under 65 that shattered the 36-hole score for a major championship.

More important to Koepka was a seven-shot lead over Jordan Spieth and Adam Scott going into the weekend. That set another PGA Championship record and was the largest at the halfway point of any major since Henry Cotton led by nine in the 1934 British Open.

Just imagine what Koepka could do if he really brings it at Bethpage Black.

“This probably sounds bad,” Koepka said, “but today was a battle. I didn’t strike it that good. The way I hung in there today and battled it, I think that was probably more impressive than yesterday, not having your `A’ game but still being able to shoot a great score.”

Koepka was at 12-under 128, breaking by two shots the record shared at all four majors, most recently by Gary Woodland in the PGA Championship last year at Bellerive.

The dominance should have looked familiar to the throaty gallery on this working man’s public course.

Bethpage Black first hosted a major in the 2002 U.S. Open, when Tiger Woods overpowered the course and the field in a wire-to-wire victory.

This time, Woods was merely along for the ride, and it was a short one.

A month after his Masters victory that made him the betting favorite at the PGA Championship, Woods started the back nine with three straight bogeys and never recovered, shooting a 73 to miss the cut for the ninth time in a major.

“I’ve enjoyed being the Masters champion again, and the PGA was a quick turnaround,” Woods said. “And unfortunately, I just didn’t play well. As I said, I didn’t do all the little things I need to do correctly to post good scores and put myself in position to shoot good scores.”

Koepka did everything right, no matter how it felt to him.

Spieth was hopeful of being in contention at a major for the first time since the British Open last summer, and he made key putts for par and a 40-foot birdie putt toward the end of his 66 to get within two shots before Koepka teed off in the afternoon. It was close enough — at the time, anyway — for Spieth to get queried about the missing piece of a career Grand Slam at the PGA.