Presnel Kimpembe pleaded to Paris Saint-Germain supporters through a megaphone following Saturday's 3-1 loss at Monaco.
The 27-year-old played the final 10 minutes at Stade Louis II as PSG's disappointing run of form continued against Les Monegasques, who moved into second place.
Christophe Galtier's side have now lost three of their seven league games in 2023, as many as in their previous 45 games in the competition.
PSG were also eliminated from the Coupe de France by fierce rivals Marseille in midweek and have a big Champions League last-16 first-leg tie with Bayern Munich up next.
As tensions boiled over in the away section, no visiting player initially went across at the full-time whistle, but Kimpembe soon took matters into his own hands.
The centre-back was handed a megaphone and, with supporters still jeering, said: "We're going to need you guys. We need you; we need everyone.
"The only thing I can say is thank you for coming. We will regroup in the dressing room and do things properly. We know we'll get moving again on Tuesday."
Asked in the mixed zone shortly after about his reaction, Kimpembe told reporters: "It was necessary. It's difficult for them.
"We know that they support us. They make the trips like us. They also pay for it. It's the least we can do to go and see them."
PSG were without Lionel Messi and Kylian Mbappe against Monaco, while Fabian Ruiz was a surprise absentee as the reigning champions were hampered by injury and illness.
Aleksandr Golovin struck early for Monaco and Wissam Ben Yedder doubled the lead before half-time, punishing an error from 17-year-old El Chadaille Bitshiabu.
Sixteen-year-old Warren Zaire-Emery briefly put the visitors back in contention at 2-1, but Ben Yedder struck again as PSG suffered successive defeats in all competitions for the first time since last March.
PSG's three league defeats in 2023 is their highest tally after seven games of a calendar year since 2010 when losing five times, but Kimpembe denied his side are in a crisis.
"It's not a crisis. The season is still long, it's not over," he said. "We know that these are not the results we had hoped for. That's how it is, it's football.
"It's up to us to wake up, to do what we need to do to be able to put in a series of good performances."
Asked to define PSG's current form, Kimpembe said: "It's a bad patch. As we know, wearing the PSG shirt is hard, it's heavy.
"You have to know how to have the right responsibilities and do what you have to do on the field."
Next week's visit of Bayern now brings even more pressure, with the German champions boasting six wins from six in this season's Champions League.
"There's no reason to be worried," Kimpembe added. "We've had six important months with nothing but wins. We shouldn't throw that away, even if it's true it's a difficult period.
"We are all aware of it. We have to stop talking, we have to act."