Charlie Wi and Jason Dufner both shot six-under 66 on Thursday to grab a share of the lead after one round of the Arnold Palmer Invitational.

They hold a two-stroke advantage over Nick Watney, who is alone in third place.

Tiger Woods, K.J. Choi and Justin Rose highlight a group tied for third at three-under.

For Woods, the round marked a return to PGA action. Two weeks ago, he withdrew from the WGC-Cadillac Championship during the middle of his final round, then announced he had a mild strain of his left Achilles tendon.

The former world No. 1 tested his Achilles earlier this week during the Tavistock Cup, and got through Thursday's opening round without an apparent issue. He carded four birdies and one bogey.

U.S. Ryder Cup captain Davis Love III is among those tied for 11th at minus- two, while Phil Mickelson struggled to a one-over 73.