American Matt Kuchar struck a bogey-free 64 to take a one-stroke lead after the first round of the Northern Trust Open, with Greg Chalmers and Marc Leishman the pick of the Australians. Entering the turn at four under, Kuchar rolled in three more birdies on his way toward the clubhouse to finish ahead of Sergio Garcia at the Riviera Country Club in Pacific Palisades, California. Garcia also struck seven birdies but a solitary bogey at the par-four 13th cost him a share of the lead as the Spaniard finished on six under overall. Chalmers endured a topsy-turvy round that included five birdies and three bogeys and left him in a tie for 18thh on two under overall. Leishman finished on the same score but could have found himself inside the top 10 were it not for a double bogey at the par-five 17th. World number five Adam Scott eagled his opening hole but found the going difficult onwards to end the day with an even-par 71. American Brandt Jobe holds outright third spot following a five-under 66 opening round, with compatriots James Hahn and Charlie Belijan a shot further back alongside Englishman David Lynn. A cluster of 10 players are next best on three under, including the likes of Lee Westwood, Jim Furyk and veteran Fred Couples.