The biggest roller coaster in the Lone Star State Thursday was not at Six Flags Over Texas, it was less than an hour away at TPC Craig Ranch, and Scottie Scheffler was on it all afternoon.

Scheffler – who ultimately shot 7-under 64 – began his round on fire, holing out from 75-feet on the short, par-4 sixth to reach 6 under through as many holes. His worst score in the first third of his round was a par at the par-4 second. Jason Day, who was playing with Scheffler, was in awe of his start.

“It's kind of hard to be patient sometimes when you're watching your playing partner shoot 6 under through six, playing some pretty top-notch golf,” Day said. “It was interesting and sometimes you've just got to admire it. He's been an impressive player since he's got on Tour, so it's nice to be able to watch that.”

The eagle at No. 6 was followed by a bogey at the seventh, which would kickstart a stretch of seven holes that the second-ranked player in the world would play in 3 over.

A series of misses with the putter caused the former Longhorn problems in the middle of his round. Scheffler missed a 7-footer at the seventh, a 4-footer at the ninth, an 8-footer at the 11^th, a 5-footer at the 12^th and a 7-footer at the 13^th.

“Yeah, I was pretty frustrated mid-round,” Scheffler said. “I didn't feel like I was doing anything wrong, I just kind of got on the wrong end of a few things, and the putts definitely weren't falling middle of the round, but the beginning and the end everything was going in. Yeah, I'll remember those putts towards the end and the beginning of the round, I hit a lot of good putts today and was fortunate to shoot a good round.”

After his drive ended up on the fringe at the short, par-4 14^th, Scheffler steadied things with a two-putt birdie before holing a 17-footer to make it back-to-back birdies at the 220-yard, par-3 15^th.

Pars at Nos. 16 and 17 set the stage for Scheffler, who now lives in the Dallas area and was clearly the most popular player on the course Thursday, to take advantage of the par-5 18^th in front of the friendly crowd.

A 288-yard drive left him 258 yards in on the closing hole and Scheffler took the headcover off his 3-wood and hit it to 15 feet, converting for a closing eagle to get within four shots of S.Y. Noh’s lead.

“It's pretty much a full 3-wood,” Scheffler said. “I actually barely caught it in the heel and fortunately got through the wind and that's one of those ones when you're hitting a shot from that far away, you're really just trying to hit it on line and see what happens. I was fortunate it finished up there about pin high and then hit a really good putt that went in.”