Rory McIlroy recorded a score of 73 after returning to complete his US Open first round at Merion.
The 24-year-old had ended Thursday on level-par, and he consolidated his position with three pars early on Friday.
However, a bogey at the 15th put the Northern Irishman on the back foot, and his poor form continued at 17.
The world number two would have been hoping to end the day with a par, but his approach to the final hole found the bunker.
His recovery out of the sand left him with a putt from 20 feet, but he was unable to hole it and he fell to tied-51st on the leaderboard.
