Marseille remains in third place in the French league after twice wasting the lead in a 2-2 draw at Rennes, with a handling error from goalkeeper Steve Mandanda gifting Rennes a late equalizer on Saturday.
Ghana winger Andre Ayew put Marseille ahead late in the first half and his younger brother Jordan Ayew restored Marseille's lead in the 82nd minute after defender Kevin Theophile-Catherine's leveler for Rennes.
But Mandanda, who has a record of making careless mistakes despite being an outstanding shot-stopper, let a soft cross from the right slip through his hands and Romain Alessandrini nodded home in the 88th.
''There's a lot of disappointment because we were 2-1 up, but before the match maybe we would have signed up for a draw,'' Marseille coach Elie Baup said. ''I'm disappointed for my players that we didn't win. You can have some regrets when you take the lead twice.''
Marseille is level with second-place Paris Saint-Germain, which has played a game less and hosts Lille on Sunday, and three points behind leader Lyon, which won 2-0 at Valenciennes on Friday.
Ironically, last weekend Marseille profited from a defensive error to score an injury-time winner against Montpellier, and just like the recent 3-1 defeat away to Sochaux Marseille also conceded a goal from a set piece.
''That's our weak link. We marked all the players in the penalty area but one player makes a run from outside the area and is totally free,'' Baup said. ''We have to start concentrating and working on set pieces again.''
Still, Baup thinks Marseille will benefit in the long run from playing the right way.
''We wanted to keep the ball on the ground, we have to repeat this kind of performance. It's encouraging for the future,'' Baup said. ''We have to keep going, even if we're disappointed with the result.''
Rennes stays provisionally in fourth place ahead of Saturday's later matches.
''They are a quality team, it's not for nothing that they're where they are in the league, and they're in the League Cup final,'' Baup said. ''They're fighting with us for a European place.''
Valbuena's delicate pass with the outside of his foot sent Andre Ayew sprinting through and he calmly clipped the ball under the body of goalkeeper Benoit Costil to give Marseille the lead in the 37th. He should have scored again moments later when Jeremy Morel picked him out in the penalty area, but he shot straight at Costil from close range.
Rennes almost equalized moments after halftime when Turkey striker Mevlut Erding broke free down the left only for Mandanda to save with his legs. But Marseille's defense was caught napping in the 58th and Theophile-Catherine was left unmarked to head into the top corner.
Alessandrini was causing Marseille's defense problems with his pace and skill, and Marseille forward Andre-Pierre Gignac blasted a shot wide after catching out the Rennes defense and charging through in the 65th, as both sides missed chances.
Valbuena helped create the second goal, releasing Morgan Amalfitano down the right and his cross was volleyed home at the back post by Jordan Ayew.
Substitute Abdoulaye Sane set up the equalizer with a surging run down the right, yet there appeared little danger as he pulled the ball back from a tight angle. But Mandanda let it slip through his fingers, it bounced back off the post and gave Alessandrini an easy header from three yards (meters) out.
''It was a great game, very intense. We were too shy in the first half, it was different in the second,'' Rennes coach Frederic Antonetti said. ''We came out on top in terms of chances and the quality of our play, but Marseille has more experience and more maturity than us.''
