Coach Mauricio Pochettino defended his decision to play Mbappe for 88 minutes even though PSG have a big game coming up against Bayern Munich in the Champions League on Tuesday.

"The best preparation for him is to be playing. He's a very intelligent lad, very mature in the way he thinks about what he does," Pochettino said.

"Our medical staff gives us a lot of information, which allows us to analyse the form of the players.

"We didn't take any risks with him, nor with any other player."

The jet-heeled forward put PSG ahead in the 15th minute.

Mbappe latched onto a pass, cut inside a defender and slotted the ball through the legs of goalkeeper Matz Sels, who could have done better.

Sels was beaten again in the 26th when winger Pablo Sarabia got past his defender on the edge of the area and drilled a low shot into the bottom corner, and Mbappe set up striker Moise Kean just before the break.

Pochettino replaced goalkeeper Keylor Navas at halftime with Sergio Rico as a precautionary measure, before their quarter-final return leg against Bayern.

Rico was well beaten by 19-year-old striker Moise Sahi's first league goal as he clipped an excellent half-volley into the top corner from a cross in the 62nd.

Pochettino took the risk of keeping Mbappe on, even though the match already looked won after Leandro Paredes hit a fine free kick 10 minutes earlier for 4-1.

Seventh-place Montpellier scored right at the start, just after halftime, and within seconds of the final whistle in a 3-3 draw with sixth-place Marseille.

Marseille coach Jorge Sampaoli was denied a fourth win in five games since taking charge when striker Gaetan Laborde scored for the hosts with a diving header in the fourth and final minute of stoppage time.

Marseille fell behind after just 28 seconds when striker Andy Delort latched onto midfielder Jordan Ferri's pass and expertly lobbed goalkeeper Steve Mandanda.

Poland striker Arkadiusz Milik equalised in the 42nd minute while Marseille went ahead on the verge of halftime when midfielder Pape Gueye finished confidently.

Ferri again played a long ball behind Marseille's defence in the 46th and Laborde took it down expertly before slotting through Mandanda's legs for 2-2.

It got worse for Marseille when central defender Duje Caleta-Car was shown a red card in the 62nd, yet they regained took the lead when substitute Lucas Perrin headed in Dimitri Payet's cross in the 70th.

Laborde had the last word, however.

Australian Associated Press