Justin Rose held a two-shot lead and Tiger Woods was grinding it out in the second round of the U.S. Open on Friday.
Rose was aggressive with the putter at Pebble Beach, opening up a three-shot lead on two occasions, only to bogey the first and fourth holes to drop back to seven under through 13.
The 2013 champion hit the turn in 34 after starting on the back nine, making gains at 15 and 18.
Rose, who led by just a solitary stroke after the opening round, dropped back to seven under when a par putt circled the cup but failed to drop at the first before hitting straight back at the second with another gain to restore his three-shot advantage.
The Englishman's lead was reduced to two again when he was unable to sink another par putt at four.
Francesco Molinari and Henrik Stenson were well poised on five and four under respectively, while Woods was fighting out - as he vowed to - on two under 14 holes into his second round, the Masters champion making just the one birdie at 11.
Two-time defending champion Brooks Koepka was also within striking distance on four under through 16.
Rickie Fowler, Xander Schauffele and Louis Oosthuizen - level on five under with Molinari and Aaron Wise (71) - tee off later in the day.