Jim Furyk stormed into a four-shot lead in the second round of the WGC-Bridgestone Invitational in Ohio.
The American hit a second straight 66 to go eight under par, four shots clear of compatriots Bubba Watson and Dustin Johnson and Ireland’s Shane Lowry.
Northern Ireland’s Graeme McDowell, who matched Furyk on day one, is one shot further back after carding a 71.
Level with McDowell on three under is first-round leader Danny Lee after the New Zealander could only manage a 72.
McDowell enjoyed a strong first round, having carded five birdies
but fell behind on Friday.
The 36-year-old has struggled for form this season, managing just one top-10 finish, and he has dropped from 20th to 60th in the rankings.
“I started on the back nine and did not play very well to be honest,” the former US Open champion told Sky Sports.
“I didn’t hit many fairways and was scrambling and scrambling and hung in there incredibly well.”