The Bulgarian appeared to be offside when he slammed home the visitors' third goal, which proved to be the difference in an exciting affair.
Monaco’s slim hopes of claiming the Ligue 1 title were maintained as it recorded a tight 3-2 success over Olympique Lyonnais at Stade de Gerland on Sunday.
Valere Germain opened the scoring for the home side early before a close-range effort from James Rodriguez took the principality side two goals clear.
Jimmy Briand replied promptly but a controversial strike from Dimitar Berbatov put Claudio Ranieri’s side out of sight before the Lyon striker added his second of the game.
Coming off an emphatic 4-1 Europa League win against Viktoria Plzen on Thursday, Lyon were caught cold at the beginning of this encounter a quick free kick from Fabinho picked out Berbatov, who set up captain Germain to open the scoring.
Matters quickly got worse for the home side as Samuel Umtiti limped off injured, with Gueida Fofana also picking up a problem later on, yet its more immediate concern was Monaco’s second goal, which arrived on 27 minutes through James.
The Colombian’s driving run started the move, which saw Germain center for the offside Berbatov to pass back to the 22-year-old to score from close range.
Lyon’s response was swift. Miguel Lopes was given plenty of room on the right and his low cross was steered past Danijel Subasic by Briand.
Shortly after the hosts had seen penalty appeals waved away at the beginning of the second half, Berbatov scored a controversial third for the visitors. James was again at the heart of things, slipping a pass through to the Bulgarian, who was again allowed to advance from an offside position to crack a fine finish into the top corner of the net.
Regardless of the score, Lyon pushed forward late and went close when a terrific Yoann Gourcuff volley flirted with the post.
Twelve minutes from the end, Briand reduced the scoreline further. Bakary Kone challenged Subasic for a high cross into the box, and when the ball broke kindly for the striker he rolled it into the corner of the net.
Despite late pressure, Lyon was unable to plunder an equalizing goal. Alexandre Lavazette perhaps had the best opportunity, but he shot high over the top from a cross. Gourcuff also had an opportunity with a free kick in the very last minute but his effort crashed straight into the wall.
Monaco is five points behind Paris Saint-Germain, which played later Sunday against Saint-Etienne, while Lyon is now eight marks off a Champions League berth with only nine matches of the campaign remaining.