Carnoustie - Zach Johnson came out firing on all cylinders in the pouring rain at Carnoustie on Friday as the 2015 Open champion moved to within one shot of overnight leader Kevin Kisner.
The 42-year-old American, sporting his trademark dark glasses even in the overcast conditions, bogeyed the first but then rattled in three quick birdies to move to four under par for the tournament at the turn. Kisner, who goes out later, sits at five-under.
Meanwhile, Rory McIlroy, the 2014 Open champion, also moved to within one of the lead as he picked up one birdie on the outward nine and then another on the tough 10th hole.
McIlroy's playing partner, Denmark's Thorbjorn Olesen, moved to three under par with two birdies in the outward nine.
In-form Italian Francesco Molinari, who edged out McIlroy in the PGA Championship at Wentworth earlier this season, also moved to three-under with two birdies in the first six holes.
Meanwhile, Englishman Tommy Fleetwood, who holds the course record here with a 63 last year, was four-under for his round after 12 holes, and three-under for the championship.
Australian Jason Day, often touted as a potential Open champion, made a move with two birdies in his first six holes to go to two-under.
However, a couple of Americans who began the day in strong positions suffered reversals of fortune.
Ryan Moore had moved to within one of the lead but his charge came to an abrupt halt with a double-bogey on the 10th hole, and he dropped a further shot soon afterwards to go to one-under overall.
And Justin Thomas sunk to four over par in total after having three consecutive double-bogeys from the sixth.
Many of the pre-tournament favourites were still to go out, although former world number one and three-time Open champion Tiger Woods dropped a shot at the second to go back to one over par.