Teenage midfielder Adrien Truffert capped a memorable Ligue 1 debut as he scored a stoppage time winner for Rennes which gave his side a comeback 2-1 victory at home to Monaco on Saturday and sent them top of the table.
Monaco, who suffered their first defeat of the season, dropped one place to fifth on seven points.
Wissam Ben Yedder fired Monaco ahead in the 28th minute with an unstoppable shot into the top right corner after two Rennes defenders collided as they tried to clear the danger and the ball fell kindly to the France striker.
Ben Yedder missed a gilt-edged chance to score the second in the 57th minute when he hit the bar from close range and Monaco ultimately paid the price after Benjamin Burigeaud also hit the woodwork with a thunderbolt at the other end.
Steven Nzonzi equalised in the 83rd when he powered a slick header into the bottom left corner after a flowing move, with the goal awarded after a VAR check showed he was onside.
The 18-year-old Truffert, who came on as a 41st minute substitute after Faitout Maouassa limped off injured, then enjoyed the brightest moment of his fledgling career.
As Rennes pressed forward for a winner, Monaco failed to clear the ball from their penalty area and Martin Terrier teed up the teenager to drive a low shot from 20 metres which squeezed through goalkeeper Benjamin Lecomte's arms.