Paris Saint-Germain were deservedly beaten by Bayern Munich in the first leg of their Champions League last-16 tie on Tuesday, but Kylian Mbappe's cameo on his return from injury gives them reason to believe they can still prevent another premature exit from Europe's elite club competition.
Mbappe did not look like a player who had been brought back much earlier than expected following a thigh injury as his electrifying pace caused panic in the Bayern defence when he came on for the final half-hour.
The France superstar could not inspire a comeback as Bayern left the Parc des Princes with a 1-0 win, but only a brave Yann Sommer save and then a marginal offside call denied him an equaliser.
"We only lost 1-0, there are no more away goals, and if we play our attacking game, cause them problems and score once, we'll be level," Mbappe said as he looked ahead to the return leg in Germany on March 8.
"We are not beaten, not at all. We still have every chance."
However, what Tuesday's game confirmed was the extent to which PSG are dependent on Mbappe, despite the presence of Lionel Messi and Neymar in their attack as well.
Messi and Neymar struggled to have any real influence on the game in the first 57 minutes before Mbappe came off the bench, by which time Kingsley Coman had put the away side ahead.
The Argentine may have just inspired his country to World Cup glory and Neymar may still be the world's most costly footballer, but there was a reason why PSG were so desperate to keep Mbappe last year when it seemed certain he would join Real Madrid.
"When he came on Mbappe completely lifted the atmosphere in the stadium and that also gave the other players a lift," admitted Bayern coach Julian Nagelsmann.
"It is clear that Kylian Mbappe can change any game."
The 24-year-old, scorer of seven goals in six matches during the group stage, now has three weeks to get back to full fitness and try to lead PSG into the quarter-finals.
Failure is almost unthinkable for a club who have never won the Champions League despite all the investment of their Qatari owners over the last 12 years, and who have gone out of the Champions League in the last 16 in four of the past six seasons.
Qatar's emir, Sheikh Tamim bin Hamad Al-Thani, was in attendance at the Parc des Princes to watch PSG suffer a third consecutive defeat, the first time that has happened since 2011, just after the Gulf state's takeover of the club.
His presence came amid intensifying speculation that Qatari investors are looking to buy Manchester United.
Whether such a move could have any impact on PSG remains to be seen, but the French champions need to turn things around in Munich next month to avoid the sense that the Qatari project is seriously stalling.
After all, they may be five points clear of Marseille at the top of Ligue 1 despite a recent slump but domestic success alone is not enough.
Nevertheless, the emir cannot have failed to notice that neither Messi nor Neymar could make a serious impact on Tuesday's match -- both were given a rating of three out of 10 by sports daily L'Equipe, as was midfield lynchpin Marco Verratti.
Messi and Neymar create another problem -- their lack of running and tracking back needs to be compensated by their teammates.
According to UEFA, Bayern's team ran nearly eight kilometres more than PSG, almost as if they had an extra player despite the Bundesliga leaders finishing the match a man down after Benjamin Pavard was sent off.
"Obviously we have identified that problem but we can't change the characteristics of the players," acknowledged Paris coach Christophe Galtier.
"We have players who like to get the ball to feet and create. That is what 'Ney' and Leo like so we need to have players who can make runs once they get the ball."
Mbappe is just that player and the second leg could be very different if he is able to play from the start.