Graeme McDowell is two shots off the lead after the opening round of the Valero Texas Open.
The Northern Irishman, who has not won on the PGA Tour since 2015, carded a four-under-par 68, consisting of seven birdies and three bogeys, to put himself in early contention in San Antonio.
McDowell is chasing South Africa's Branden Grace, whose 66 sent him one-shot clear at the summit. Grace also fired seven birdies, with a solitary bogey.
American trio Will MacKenzie, John Huh and Stewart Cink and Australian Steven Alker are all on five under while McDowell is one of 13 players on four under.