Carnoustie - Northern Irish star Rory McIlroy put pressure on overnight leader Kevin Kisner at the Open on Friday in inhospitable weather conditions at Carnoustie.
The 29-year-old four-time major champion was four under par, a shot behind Kisner, after 15 holes of his second round.
He had been level with the American leader after successive birdies at the 13th and 14th holes, only to drop a shot at the par-four 15th.
Kisner, who shot a 66 on Thursday, tees off at 13:53 in his second round.
Seeking his first major in four years, McIlroy was not the only player making a move in the rain.
Englishman Tommy Fleetwood - who holds the course record on the Scottish links - was also a shot off Kisner after moving to five-under for his round.
McIlroy's successor as Open champion in 2015, American Zach Johnson, was also on four-under overall after 13 holes.
Meanwhile, 14-time major winner Tiger Woods endured a rollercoaster start to his round, recording successive bogeys at the second and third, before rectifying that with consecutive birdies to return to even par for the tournament.