Kylian Mbappe admitted that he was "not supposed to play" in Paris Saint-Germain's Champions League round of 16 first leg against Bayern Munich on Tuesday. Mbappe came off the bench but was unable to prevent a 1-0 loss at the Parc des Princes.

The France forward suffered a hamstring injury Feb. 1 that the club initially said would rule him out for three weeks. Yet he came on as a substitute in the 57th minute and ignited the game, having two goals disallowed for offside as his entrance changed the storyline of the match.

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"It was difficult, unpredictable," Mbappe said. "I wasn't supposed to play but I wanted to play and help my mates.

"We did everything, we worked night and day to get me some game time. I wanted to [start the game]. But sometimes you have to be satisfied with what you can do, and that's all I could do."

After Kingsley Coman scored the game's only goal in the 53rd minute, Mbappe's return to fitness is PSG's best hope looking ahead to the March 8 second leg at the Allianz Arena. And Mbappe believes that if PSG are at full strength, they can turn things around in Munich.

"We have to remember the final part of the game; we're behind but we saw that we were able to cause them trouble," he said. "We need all our players to be healthy and go there to win and qualify.

"We saw that when we are all together we are able to play forward, to play attacking football and that they were not comfortable."

Veteran defender Sergio Ramos, though, was more pointed in what PSG need to change if they are to reach the last eight.

"I'm very disappointed for the supporters," he told Canal+. "We'll have to show more character in the second leg, and more verticality.

"We want to win and be the best we can be, but this is the nature of football. Sometimes we play well, sometimes we play badly. What counts is the final result. The more we play, the more experience we'll have. It will get better and better."

Coach Christophe Galtier will also hope that Achraf Hakimi will be back on the right flank of the defence after he was replaced because of injury at half-time.

"I was counting on him but it quickly became evident that he could not play the whole game," Galtier said.

"We took a risk with him but he quickly suffered from muscle pains."

Galtier has hopes that the story will be different in three weeks in Munich.

"It's another game. Tonight, nobody is out, nobody is through," he said. "I have a lot of hope. I hope we will have a lot of fresh players and that we will be able to play the way we played the last 20-25 minutes."

Information from Reuters and The Associated Press was used in this report.