Paris Saint-Germain extended their lead at the top of Ligue 1 with a 3-1 win at Montpellier on Wednesday but their evening was overshadowed by an injury to Kylian Mbappe, who had earlier missed a penalty. The France superstar had an eighth-minute spot-kick saved by Montpellier's Benjamin Lecomte and then remarkably saw his second attempt turned onto the post by the goalkeeper after the referee ordered a retake, AFP said. Mbappe then limped off with what looked like a hamstring injury midway through the first half, raising the alarm for PSG with the first leg of their Champions League last-16 tie against Bayern Munich now less than two weeks away. Speaking after the game, coach Christophe Galtier suggested the injury was down to a knock rather than a muscle problem. "He took a knock to the back of the knee or the back of the thigh, so we'll see," said Galtier. "I'm not too worried," he added. "It's a bruise or a contusion, we don't know yet. "With the run of matches we don't want to take risks with a very busy fixture list, but it doesn't appear that serious." PSG host Bayern in Paris on February 14, with the second leg in Germany on March 8. They are desperate to avoid a repeat of last season when they were knocked out at the same stage of the Champions League by Real Madrid. After winning just one of their last four league games, Wednesday's awkward trip for PSG saw them also lose Sergio Ramos to injury and have two goals disallowed before Fabian Ruiz put them ahead 10 minutes into the second half. - Messi on target - Ruiz then set up Lionel Messi to make it 2-0 with a deft finish in the 72nd minute, the Argentine scoring his 14th club goal of the season. Sixteen-year-old midfielder Warren Zaire-Emery made sure of the win in stoppage time after Arnaud Nordin -- a friend of Mbappe's from their time together at France's national training academy -- had pulled one back. PSG, who were without the rested Neymar, extended their lead at the top of the table from three to five points after Lens lost 1-0 at home to Nice. "It was a good performance in general," Galtier said. "There was an incredible scenario in the first half with the retaken penalty, we hit the post, had goals disallowed and two injuries because Sergio Ramos was involved in a collision and on falling he hurt his adductor, but apparently it is nothing serious." The win for PSG came after a frustrating end to the January transfer window on Tuesday as they failed to process the paperwork to complete the loan signing of Hakim Ziyech from Chelsea after the Moroccan winger had passed a medical. Gaetan Laborde scored the only goal of the game for Nice as Lens dropped points at home for the first time this season after winning all 10 previous matches there. Marseille climbed above Lens into second place thanks to a 2-0 victory at Nantes earlier, secured by an own goal from Joao Victor and then a late strike by Azzedine Ounahi, the Moroccan World Cup star making his debut after signing in the January window. Monaco in fourth beat Auxerre 3-2, while fifth-placed Rennes eased to a 3-0 win against struggling Strasbourg. On-loan Arsenal striker Folarin Balogun followed up his last-gasp equalizer against PSG at the weekend by netting a hat-trick as Reims came from two goals down to beat Lorient 4-2 and extend their unbeaten run to 15 games. Bottom side Angers suffered a new French top-flight record 13th consecutive defeat as they conceded in stoppage time to lose 2-1 at home to Ajaccio. That result leaves them 11 points from safety.