MIAMI: Ryan Brehm fired five birdies in a four-under par 68 on Saturday to push his lead in the US PGA Puerto Rico Open to three strokes over fellow American Michael Kim.

Kim, who trailed by one through 36 holes, fired a two-under par 70 at Rio Grande to stand alone in second, one stroke in front of Chad Ramey, Andrew NOvak, Tommy Gainey and Max McGreevy.

Brehm capped his round with an unlikely birdie at the 18th, where threaded his second shot through the trees and rolled in the putt.

"I really wanted to make that one," Brehm said of the putt. "I'm standing over it reading it and my legs were shaking pretty good, but put a good stroke on it, the putt did exactly what I thought it was going to do, break a little left to right and it went right in the middle."

Brehm is making his final start on a minor medical exemption.

A first US PGA Tour title on Sunday would give him full tour status for the remainder of the season. Solo second would still give him limited playing privileges for the rest of the campaign.

Kim, meanwhile, is seeking a second US PGA Tour title, after his victory in the 2018 John Deere Classic.

On 204, he was oen stroke in front of a quartet of players: Chad Ramey, Andrew Novak, Tommy Gainey and Max McGreevy, in the tournament being played opposite the Arnold Palmer Invitational at Bay Hill.