ARDMORE, Pa. — Tied for the U.S. Open lead, Hunter Mahan was on cruise control.
He was the steadiest player for most of Sunday at Merion Golf Club, ripping off par after par after par to stay in the hunt.
Then he hit No. 15.
Mahan's tee shot sailed into the rough. So did his second. Just like that, Mahan's Open run was over.
He fell from a three-way tie for first after his double-bogey on 15 and finished in a four-way tie for fourth with a 5-over 75 and a 285 total. It was his best Open finish since he was sixth in 2009.
"It was brutal out there," Mahan said. "It was tough finishing. But I swung it pretty well, kept my composure."
He scored pars on 13 of his 14 holes with one bogey and tied for the lead with winner Justin Rose and Phil Mickelson going into 15, where he three-putted for double bogey.
He rebounded with a par on 16, but bogeyed the next two holes and lost any chance of winning his first major.