Jordan Spieth delivered a putting masterclass on the way to setting the clubhouse lead in the weather-hit Pebble Beach National Pro-Am on Friday before second-round play was suspended due to thick fog on the Monterey Peninsula in California.
The world number six fired a seven-under-par 65 at Spyglass Hill, one of three venues being used for this week's PGA Tour event, to post a 10-under total of 133 before play was halted with only 33 players back in the clubhouse.
Derek Fathauer was also at 10 under but had one hole to play at Pebble Beach while Australian world number one Jason Day was at nine-under with six holes remaining at Spyglass Hill.
"I have been striking it well," Spieth told reporters after ending his round at the par-four ninth with his eighth birdie of the day. "I've been trying to do a lot of work with the putter and we've got some pure greens out here at Spy.
"I started to roll some putts in, starting on our third hole of the day, number 12. So I got into a nice rhythm, the hole started to look big towards the end and I'm very glad to finish with a nice three."
Organisers were trying to get the tournament back on track after the opening round, which was suspended on Thursday because of heavy rain, was finally completed mid-morning on Friday.
However, fog then delayed the scheduled start of round two before later forcing play to be suspended for the day at 4:21 p.m. PST (2121 GMT).
The second round is scheduled to resume at 7:30 a.m. on Saturday, with sunny weather forecast for the rest of the weekend.
Spieth was among 81 players who had to return to the course on Friday to complete round one, and he parred his last two holes at Monterey Peninsula Country Club for a 68 to sit one stroke off the lead.
He then headed out to Spyglass Hill where he moved to the top of the leaderboard by shooting a sparkling 65 that included a 12-foot birdie putt at the par-four second and a 25-footer at the par-four fourth.
"Conditions were all so totally different ... maybe because we got so much rain during the round yesterday," double major champion Spieth said of the switch from Monterey Peninsula Country Club to Spyglass Hill.
"So much could happen with three courses. The first two rounds, it’s been easy. Tomorrow might feel a little different."
(Reporting by Mark Lamport-Stokes in St. Augustine, Florida; Editing by Peter Rutherford)