Jacobsen is aiming for a first win in eight years

The 49-year-old, who led by one at the halfway stage, stayed on course for his first win on the PGA Tour since 1995.

But Chris Riley, after a superb 63, and Willie Wood are within striking distance, with Kenny Perry - a three-time winner this season - and Craig Barlow a further shot back.

Jacobsen is aiming to become the sixth player aged 40 or older to win this season, the most recent being 50-year-old Craig Stadler's victory in last week's BC Open.

ROUND ONE LEADERBOARD (US unless stated) -11 P Jacobsen -10 C Riley, W Wood -9 C Barlow, K Perry -8 D Stiles, JJ Henry, R Damron Full scoreboard

"It gives me hope," Jacobsen said. "I don't know why anybody would limit themselves by age or inexperience.

"Ben Curtis didn't let inexperience get in his way when he won the (British) Open and Stadler didn't let age get in his way when he won last week."

Jacobsen bogeyed the par-three 11th and par-four 14th but rallied with birdies at the 15th and 16th to get under par for his round.

Wood was on 13-under and holding a three-stroke lead after the 13th, but saw that evaporate with a bogey at the 14th and a triple-bogey at the par-four 15th.

Riley, after missing five cuts in his last seven tournaments, needed just 22 putts to post the lowest score of the day.