(REUTERS) - Swede David Lingmerth limped to a three-over par 73 on Saturday but it was enough to keep him at the top of the PGA National leaderboard heading into Sunday's final round.

On a day that featured soaring scores for the final groups and a rain delay of more than an hour, Lingmerth rebounded from an early double bogey to stay on top by one shot at TPC Potomac in Maryland.

Lingmerth sits at seven under for the tournament ahead of American Daniel Summerhays, who shot even-par 70 to remain at six under.

"It's not the day I wanted but I think I'm right where I need to be for tomorrow," Lingmerth told reporters on Saturday.

"You have to be in the fairway here to score. I struggled with it. It was a tough day."

American Spencer Levin produced the day's best round with a five-under 65 and is two shots back of the Swede.

A group of three players is at four under including Australian Geoff Ogilvy, who failed to record a single birdie in his four-over 74.

World No. 9 Rickie Fowler of the US fired a 68 to climb to even par.

World No. 99 Lingmerth, whose only PGA Tour victory came at the 2015 Memorial Tournament, struggled with pulled shots throughout the day.

He bogeyed the first and made a double at the fourth but still led by two until a bogey at the par-3 17th tightened the tournament to one shot.

"I felt pretty good to begin with but got myself into some trouble," Lingmerth said.

"I think my tempo was a little bit off with the driver today."

Summerhays, looking for his first win on the PGA Tour, kept the pressure on with a steady round that featured a birdie and a bogey.