By Mark Lamport-Stokes OAKMONT, Pennsylvania (Reuters) - Dustin Johnson ended a marathon Friday at the weather-disrupted U.S. Open with the clubhouse lead, carding one-under-par 69 shortly before second-round play was suspended for the day in fading light. The long-hitting American, who missed a three-foot putt at the final hole to hand last year's U.S. Open to Jordan Spieth, produced superb form from tee to green to post a four-under total of 136 at Oakmont Country Club. Also at four-under was surprise first round leader Andrew Landry, a PGA Tour rookie who will only start the second round on Saturday morning after the year's second major championship was knocked off schedule by multiple thunderstorms on Thursday.
