LE HAVRE, France - French champions Paris St Germain won 4-1 at Le Havre on Friday, capitalizing on a late collapse by the hosts to get their Ligue 1 season off to an excellent start.

PSG opened the scoring after three minutes when Goncalo Ramos found Lee Kang-in inside the box and he sent a left-foot shot into the net.

The visitors' joy was short-lived, however, as Ramos was hurt in a challenge and the Portuguese international had to be replaced by Randal Kolo Muani.

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The hosts shocked PSG after the break as Gautier Lloris equalized three minutes in, before Josue Casimir's goal was disallowed following a VAR decision for handball in the build-up.

Five minutes before the end of the game, however, the Le Havre defense went missing.

Ousmane Dembele headed home five minutes from time, Bradley Barcola added a third and Kolo Muani completed the rout from the penalty spot.

PSG coach Luis Enrique was pleased with his team's performance.

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"It wasn't easy at all," he told reporters. "Maybe we started too calmly. We scored a goal very quickly and that relaxed us a bit too much."

The injury to Ramos was, however, a serious blow to PSG.

"I’m not a doctor but I think it looks like a serious injury. I don’t know how many weeks he will be out," Luis Enrique said.