Danny Lee joined Alex Noren at the top of the leaderboard as the Aberdeen Asset Management Scottish Open set itself up for a dramatic conclusion at Castle Stuart Golf Links.
There were nine players within two shots of the lead as the final group reached the back nine on a rainy day in the Scottish Highlands.
Noren played the front nine in level par to stay at 12 under but a third birdie of the day for Lee on the tenth saw the New Zealander take a share of top spot.
Lee and Noren both have European Tour wins - as does Andy Sullivan who is just a shot back - while the other man at 11 under, Tyrrell Hatton, is searching for a first title.
Callum Shinkwin was then at ten under having set the clubhouse target with a 65, alongside Matteo Manassero, Graeme McDowell, Richie Ramsay and Justin Walters.
Hatton, Ramsay, Manassero and Walters were all in line to qualify for next week's Open Championship at Royal Troon.
Ramsay was the first player to make a real charge up the leaderboard as he looked to become the first Scottish winner of this event since Colin Montgomerie in 1999.
He made a run of four birdies from the third - the highlight being a stunning 45-foot putt on the fourth - to get to ten under.
McDowell made a textbook birdie on the first to get to nine under and he was soon joined by Sullivan who took advantage of the third. Sullivan's playing partner Lee also birdied the third to join Ramsay, Hatton and Manassero at ten under.
That was soon three back, though, as Noren put his approach on the second to two feet and made a birdie to get to 13 under.
Walters then made his move with back-to-back birdies on the third and fourth to take second place all on his own.
Ramsay got in bunker trouble over the back of the seventh to drop a shot but Sullivan took his place in the group at ten under with a birdie on the fifth.
McDowell made a further gain on the sixth to also get into a share of third alongside Shinkwin, the Englishman making birdies on the 16th, 17th and 18th to set the target.
Lee's birdie on the sixth moved him to 11 under and it was all happening on the eighth where Sullivan and Hatton both made birdies and when Noren dropped a shot on the same hole, the gap was one.
That birdie on the tenth then moved Lee to 12 under and Noren was reined in.
Ramsay had birded the same hole to get back to ten under, while Manassero had ten straight pars. Walters had dropped back into that group with a bogey on the sixth.