Thomas and Scott held the 36-hole lead at 11 under as third-round play was set to begin Saturday afternoon.
LOS ANGELES — Justin Thomas nearly holed a 9-iron for birdie, and then made par by hitting a flop shot from the putting surface over the bunker on the par-3 sixth at Riviera, to cap off a 6-under 65 and share the lead with Adam Scott at the rain-delayed Genesis Open.
Scott, playing one group behind Thomas, also had one birdie in the six holes he played Saturday morning for a 65.
They were at 11-under 131, one shot ahead of J.B. Holmes (69) with the half of the 144-man field just starting the second round.
Tiger Woods made a 25-foot birdie putt from the fringe on his final hole for a 71 that at least gave him a chance of making the cut. Conditions were frigid in the morning, but otherwise calm and getting warmer. Throw in soft conditions from rain, and it was ideal for scoring.
The start of the tournament was delayed seven hours by rain. The 36-hole cut was expected Saturday afternoon, with everyone facing a marathon finish on Sunday.
''It's going to be a nice day. I'm glad to be part of it going this afternoon and tomorrow,'' Woods said, confident that he would be playing.
Thomas could barely feel his toes when he went to the range with a hoodie over his cap. He resumed the second round on the par-3 fourth, the 218-yard hole that felt even longer.
''The hard part of warming up was I knew my first shot was a 3-iron. Hitting those on the range was tough,'' Thomas said. ''I think it was 42 degrees. My toes are still tingling. Pretty much right when we finished is when it got nice. I hope those guys enjoy it.''
Scott made a 15-foot birdie on No. 5 and holed some 3-to-4-foot par putts to keep his round going.
Rory McIlroy came to life with an 8-under 63. He started by making a 20-foot birdie on No. 4, made another from 30 feet on No. 5 and made two more birdies with a tap-in on the seventh and a 30-footer on the eighth.
''Successful morning,'' McIlroy said. He was four shots behind.
Thomas dealt with the chill and was helped by the soft course, and that was evident at the par-3 sixth, famous for having a bunker in the middle of the green. The pin was front right. Thomas went back left.
''I was so cold,'' he said. ''We were in the sun on No. 5, and I got to 6 and ... I don't know if it was being so cold or what, but I tried to hit a cut and double-crossed it.''
Instead of putting high over the bunker and trying to use the slope back to the pin, he used his 60-degree wedge and clipped a flop shot so perfectly he didn't even leave a divot. The ball cleared the bunker easily and stopped quickly, leaving him a short putt for par.
''I couldn't have done that without the course being soft,'' he said.
But soft and cold added another element to Riviera. Thomas, one of the longer hitters on the PGA Tour, had to hit fairway metals twice into par 4s - a 5-wood from 222 yards at No. 2 to 10 feet for birdie, and a 5-wood from the right rough on No. 18 that led to bogey.
It brought back memories of his junior days, when he was much smaller and much shorter. He would go to junior tournaments, call home and his father would ask for ''the number.'' The reference was how many par 4s where Thomas would have to hit a fairway metal.
''I was probably 11 the last time I did that,'' he said.
Woods made an eagle on the par-5 opening hole - his 10th of the second round - in the cold and rain Friday night, followed by two straight bogeys to end his long day of 30 holes, the most he has played since returning from a fourth back surgery. And then he opened with another bogey on No. 4 and had to make a 6-foot par putt on No. 8 when he was too aggressive with his 30-foot birdie putt.
But he made the putt at the end, leaving him at least 10 shots behind at 1-under 141, and having to wait to see if he gets a tee time later Saturday afternoon. Woods last year missed the cut at Riviera, the course he has played the most times (nine) without winning.