By Mark Lamport-Stokes OAKMONT, Pennsylvania (Reuters) - When the opening round of the weather-hit U.S. Open was finally completed on Friday, the unlikely leader was PGA Tour rookie Andrew Landry, who held a one-stroke advantage with several big names in hot pursuit. Landry, competing in his first U.S. Open, had set the pace earlier on an overcast morning as he birdied his final hole for a four-under-par 66 at the rain-softened Oakmont Country Club. American Dustin Johnson and England's former world number one Lee Westwood, each seeking a first major title, carded 67s while Spaniard Sergio Garcia, winner of the AT&T Byron Nelson in his most recent start, was among a group of three players on 68. More...