Rod Pampling and Marc Leishman on the trail of leader Charley Hoffman in Connecticut PGA event

Charley Hoffman fired a 9-under-par 61 to seize a one-stroke lead over fellow American Hunter Mahan after round one of the PGA Travelers Championship in Connecticut.

Hoffman, who shared 45th at last week's US Open, eagled the par-four 10th and par-five 13th holes and after a birdie at the 15th needed to birdie the last three holes to match the USPGA's all-time record low round of 59.

He only managed a birdie at the 18th, but it was enough to put him atop the leaderboard by a stroke over Mahan, who shared fourth at the US Open, and two shots over 2012 Masters champion Bubba Watson.

Australia's Rod Pampling is in a group of six players in equal fourth place after shooting a 5-under 65.

Pampling's countryman and defending champion Marc Leishman opened with a 4-under 66. He finished one stroke ahead of Mahan and Hoffman last year to capture the crown at the TPC River Highlands for his first US PGA victory.

US Open winner Justin Rose of England fired a 3-under 67 to share 18th.