Kevin Kisner, despite a double bogey at the last, signed for a 1-under 70 to hold on to a share of his overnight lead alongside 2015 champion Zach Johnson (67).
But it is four-time major winner Rory McIlroy (69) and defending champion Jordan Spieth (67) who most are taking a keen interest in as both made a Friday move to be in position for a weekend charge.
The leading trio are at 6-under, trailed by Tommy Fleetwood, Pat Perez and Xander Schauffele at 5-under and sharing third.
McIlroy is among a group of five players at 4-under while Spieth is alongside Rickie Fowler and Kevin Chappell at 3-under.
Just 28 players remain in red figures through 36 holes, a total of 79 qualifying for the weekend at 3-over or better.
Among them are eight of the 10 Australasians in the field, Adam Scott, Jason Day, Lucas Herbert, Cameron Davis, Marc Leishman, Cameron Smith, Brett Rumford and Ryan Fox all qualifying for the weekend. (Read Bruce Young’s full wrap of their play here.)
The baked out Carnoustie course was a less fiery prospect on day two with overnight rain extending into the morning and taking the edge off the speed of the fairways.
Softer greens were also a result but, interestingly, the course played slightly more difficult with the lead only moving from 5-under overnight to 6-under with two rounds to play.
England’s Tommy Fleetwood, favoured by many before play got underway, had the round of the day with a 6-under 65, one better than the next best returned by Xander Schauffele.
Among those posting 67 were Zach Johnson and Spieth and there were a total of just 19 players breaking 70.
But for all the numbers it is the play of the world’s best known that intrigues and it was a mixed bag at this 147th Open.
World Number One Dustin Johnson and the man immediately behind him in the rankings, Justin Thomas, both missed the cut.
World Number Three Justin Rose was on track to join them before making three at the last to sneak in on the number, his second straight birdie on the hole and one of only 34 made from 312 attempts in the opening two days.
Also having the weekend off are Sergio Garcia, Hideki Matsuyama, Russell Knox, Jon Rahm and Bubba Watson.
60-year-old Bernhard Langer continues to amaze after making the cut for the 25th time in 31 starts and will start Saturday in a share of 52nd position at 2-over.
Tiger Woods signed for a second consecutive even par 71and at T29 is far from out of the tournament though continues to take two steps forward and one back.
The three-time champion offset four birdies with four dropped shots in a repeat of his day one effort where he had three of each.
“I played a little bit better yesterday,” he said after the round. “Today wasn't quite as good, but I finally birdied the par 5. So that's a positive.
“Right now I'm six back, and by day's end, I think I'll be more than that. It will be a pretty packed leaderboard, and I'm certainly right there in it.”
He was ultimately wrong about being further back though the leaderboard is definitely packed, 28 players within five shots of the lead.
For his part McIlroy was pleased with his day two play given the starkly different course conditions affecting his aggressive game plan.
“Under those conditions, I would have taken that score today going out,” he said of his 2-under 69.
“It wasn't that bad, but it was just damp enough and cold enough that the game plan that I was trying to adapt to be aggressive and hit driver a lot, I just couldn't do it.
“All the bunkers were in play. And then with it being wet, with the ball being wet and the club face, the possibility of that getting wet, you know, the spin rate goes right down on the driver, and it could start to go either way.
“So a lot more irons off tees and a lot more conservative, but ended up being the same score. So I'm pretty pleased with that.”
Spieth, too, was happy to get under par despite not having his ‘A’ game.
“I hit a lot of drivers today,” he said, “even though I wasn't driving it very well, I was at least hitting short irons into the greens out of the fescue.
“I was able to make a couple of holes. I stole 10 and 11. I could have ended up a couple over there and ended up a couple under. And then played smart from there on out.”
FRIDAY MORNING HIGHLIGHTS FROM CARNOUSTIE:
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