Nicky Clark came off the bench to score the winner for Dundee United which ended Ross County's unbeaten start to the season.
Former United defender Coll Donaldson opened the scoring for the Staggies with a stunning 20-yard low drive against his former club just before the half-hour mark.
But the visitors levelled five minutes before half-time through Peter Pawlett and then Clark completed the turnaround 11 minutes from time.
Ross County made two changes to the team that drew 2-2 with Kilmarnock on Wednesday night, with midfielder Harry Paton replacing Regan Charles-Cook and striker Billy McKay back in the starting XI at the expense of Josh Mullin.
The visitors made four changes to the team that lost 1-0 to Hibernian with Adrian Sporle, Logan Chalmers, Calum Butcher and Kieran Freeman coming in. Lawrence Shankland remained out with an ankle injury.
County created the first chance of the match when teenage full-back Josh Reid exploited space down the left wing. His cross into the box found Michael Gardyne eight yards in front of goal, but he could not guide his header on target.
The Staggies appealed for a penalty in the 22nd minute when Paton claimed he was tripped by Mark Connolly, but he was booked for simulation.
But the hosts did forge ahead after 29 minutes. Iain Vigurs' cross was headed out of the box by Louis Appere, but the ball fell to Ross Stewart who laid up Donaldson to fire a low volley from 20 yards out past Benjamin Siegrist into the bottom-right corner.
The lead did not last long, though, with United levelling in the 40th minute when Luke Bolton's cross from the left wing was met by Sporle. His shot was blocked by the defence but the ball fell kindly to Pawlett to fire home from close range.
Dundee United had a golden chance to take the lead on the hour mark following a counter-attack, Appere releasing Bolton who was one on one with Ross Laidlaw but the goalkeeper did well to block his low shot.
Bolton went close again when he got the better of the Staggies' defence to run on to a long ball and beat Laidlaw but his shot fizzed wide of the left post.
But the winner did arrive 11 minutes from time when Cammy Smith's pass into the box found Clark unchallenged and he fired past Laidlaw from eight yards out to give the visitors all three points.