The leaderboard was a movable feast throughout a low-scoring Friday and moving day will see a vast array of challengers jostling for position.
Rory McIlroy is well set and there are a handful of others ready to mount their own surge and put pressure on leader Cameron Smith. Ahead of a super Saturday at St Andrews, here are six to keep an eye on…
There would be few more popular winners than Rory McIlroy among the Old Course faithful and he looks in the mood to reward them.
He has showcased his undoubted quality at every major this year – and looks set to complete a clean sweep of top 10 finishes for the first time – but has not yet strung it together across the four days. Could this be the week his fortunes change?
The man himself is retaining hope and said following his second round 68, which took him to -10 for the week: “I know I've got the game.
“That's all I need. I just need to go out and play my game and play my golf over the next two days and that's all I can do.
“Cam Smith goes out and shoots another two rounds like he did the first two days, I'm going to have a really hard time to win the tournament.
“I've just got to go out and do the best I can and worry about myself and hopefully that's good enough.”
McIlroy knows what it takes to win back-to-back majors, having done so in 2014, and Matt Fitzpatrick is looking to follow in his footsteps.
A level-par round on Thursday left him with work to do but he has put himself in contention to challenge following a six-under-par 66 which saw him comfortably outperform playing partner Tiger Woods – something a young Fitzpatrick could only have dreamed of.
His Hallamshire clubmate Barclay Brown - the frontrunner for the Silver Medal - starts from the same -6 score as the battle for Steel City bragging rights heats up.
The 2017 Champion Golfer has not yet caught fire on the Old Course but he has demonstrated the occasional glimpse of his undoubted class.
At nine shots off the lead, mounting a serious tilt for a second Claret Jug could be beyond him but it would not be a surprise to see Spieth start climbing the ranks on Saturday.
Few can get on a roll like the Texan, who was runner-up at Royal St George’s last year and will hope to have a say in the final day once more.
One of several Australians to shine at St Andrews so far this week, Adam Scott has given himself a chance of finally laying to rest the ghosts of 2012.
A superb seven-under-par 65, including three straight birdies around the turn, saw him rocket up the standings as his trademark long putter delivered the goods.
Scott, who looked set to lift the Claret Jug nine years ago only to dramatically let his advantage slip to Ernie Els, said: “Anytime I think about letting one slip through my hands, it hurts.
“It would be exciting if I shot a really great round tomorrow to tee off with a legitimate feeling that I'm in contention.
“Not only for the fact that I have not really been in that position for a major for a little while, but also for the fact that I have had one hand on this jug, I feel like, and I would like to put two on.”
A two-time winner of the Alfred Dunhill Links, Tyrrell Hatton likes the Old Course – but this is third time lucky when it comes to making the cut at an Open here.
He got there with plenty to spare courtesy of a six-under-par 66, which contained no dropped shots, as he went toe-to-toe with world number 1 and playing partner Scottie Scheffler, who also goes into the weekend on eight-under-par.
Hatton is the best-placed of the English contingent and will back himself to better his best Open finish of T5.
Neutral observers relish getting behind a home favourite and an underdog – David Law ticks both boxes.
Law’s first ever round on the Old Course, 13 years ago, was one to forget as he shot 85 but the world number 351 looked in fine form on Friday as he signed for a 69 to follow his level par opening round.
The 31-year-old spent the afternoon with his children at the park and will hope to reap the rewards of his rest when he sets out for the weekend – no doubt backed by plenty of hearty Scottish voices in attendance.