Kingsley Coman scored the only goal of the game in the 53rd minute at the Parc des Princes, four minutes before Mbappe – returning from injury – was brought on in the last-16 clash.

The France international remained a doubt before kick-off but spurred a struggling PSG into life after his substitution, twice seeing goals ruled out for offside in the first leg.

While the Ligue 1 champion will head to the Allianz Arena on 8 March with a slender 1-0 deficit, Galtier reminded PSG it will be all to play for in Germany.

"We managed to push them over 25-30 minutes," he said. "There is the offside goals, two or three situations.

"There is obviously a disappointment, but we know that there is not a qualified team or a team eliminated tonight.

"We will have to see in three weeks the state of our team, if we will have recovered fitness and have players to play a full match at the level of our last half hour."

A late rallying performance from Mbappe and Co. will offer Galtier reason for optimism, especially given PSG overcame Bayern in the two-legged Champions League affair in the 2020-2021 season.

PSG downed then-defending champion Bayern on away goals in the quarter-finals, with a 3-2 away victory enough to stave off the Bundesliga side's 1-0 win in the return meeting.

Mbappe scored twice in the first-leg victory in that season and Galtier labelled it as unfortunate PSG's planned introduction of the forward came just before Coman's strike against his former side this time.

"From the moment we didn't have depth in our game, Bayern advanced and put pressure on us and we had trouble getting the ball out, holding it very high," Galtier said. 

"We had a very difficult first half. There was another scenario planned because I knew that I was going to be able to use Kylian.

"Unfortunately, we conceded this goal just when the changes were going to take place with a new organisation.

"There were 25 minutes where the team reacted but in a system that corresponds more to our qualities."