World No. 1 Brooks Koepka made his first appearance of the new PGA Tour season a brief one when he missed the cut at the Shriners Hospitals for Children Open ion Friday.

Koepka added an even-par 71 to his opening 70, falling four shots short of qualifying for the weekend at TPC Summerlin on a day when four players shared the halfway lead.

After more than a month off since the Tour Championship, Koepka hardly looked fazed as he shook hands with playing companions Gary Woodland and Adam Scott at the final green.

He shrugged off his first missed cut since March as nothing to be concerned about, promising better things ahead in a fortnight when he defends his title at the CJ Cup @ Nine Bridges in South Korea.

"I'm not disappointed. I feel very, very close. I'm just fine with where my game is. It will be good for Korea," he said.

"I'm pleased the things I've been working on, wedges, distance control, spin control were spot-on this week so I'm very pleased with it."

Koepka acknowledged not making a lot of putts, and speculated that his green-reading skills were a bit rusty.

Atop the leaderboard, local resident Kevin Na shot the day's best score, a 62, to join fellow Americans Lucas Glover (63), Patrick Cantlay (64) and Brian Stuard (65) at 12-under 130.

Na has good memories of a course where he notched his first PGA Tour victory in 2011, and he certainly knows the lay of the land around and on the greens.

He sank three putts from longer than 35 feet, including a 60-foot monster at the first hole.

"I know the greens can be a little bumpy in the afternoon but I was making putts," he said in what might qualify as a significant understatement.