With his team trailing 2-1 and Paris Saint-Germain pushing hard for another goal, Barcelona coach Xavi Hernández's substitutions paid off immediately.
Midfielder Pedri set up the equalizer for Raphinha within a minute of coming on at Parc des Princes stadium.
Then, two minutes after his introduction, central defender Andreas Christensen headed home from a corner to give Barcelona a 3-2 win in the first leg of their Champions League quarterfinal on Wednesday.
"Pedri came on and helped us a lot. I'm very proud of the team. Christensen also came on and helped," Xavi said. “Tactically we did really well.”
Raphinha was the pick of Barcelona's players on the night, and the Brazil forward had scored twice before Christensen's 77th-minute goal.
The imposing Christensen headed Ilkay Gündogan's corner from the left past Gianluigi Donnarumma from close range as the PSG goalkeeper stood rooted to his line instead of challenging for the ball.
After that goal, PSG coach Luis Enrique's head dropped.
“We made things a bit difficult for ourselves. We managed to turn things around in the second half and could have had a third (goal),” Enrique said. “Everything's still open for us and we will go there with ambition.”
Raphinha's lively performance and finishing contrasted with a lackluster performance from Kylian Mbappé, who has scored a club record 251 goals for PSG but did not hit the target this time or make many of his trademark electric runs from deep.
Raphinha opened the scoring in the 37th and Ousmane Dembélé equalized in the 48th against his former club. Three minutes later, midfielder Vitinha put PSG ahead from Fabián Ruiz's pass in a pulsating match where Dembélé hit the left post moments before Christensen's goal.
Raphinha curled Barcelona ahead after Donnarumma struggled with Lamine Yamal's slick right-wing cross, which the 16-year-old Spain winger exquisitely flicked with the outside of his left foot.
Sloppy defending from both sides followed.
Mbappé's left-wing cross was hacked clear by Ronald Araújo and fell to Dembélé, who cut inside Frenkie de Jong and slammed the ball past goalkeeper Marc-André ter Stegen.
Vitinha was afforded too much space from Fabián Ruiz's pass, and slid a shot under his body.
Raphinha read substitute Pedri's superbly weighted long pass and clipped a volley past Donnarumma, making it 2-2 in the 62nd ahead of Christensen's winner. Raphinha turned and stood still, arms crossed, defying the PSG crowd jeering him.
A fan ran onto the field seconds after the final whistle but was quickly caught by stewards.
The return leg is next Tuesday in Spain.
In the other quarterfinal Wednesday, Atlético Madrid beat Borussia Dortmund 2-1 at home.
The rivalry between PSG and Barcelona has intensified in recent years, with Barcelona again in the driver's seat.
PSG knocked Barcelona out in the round of 16 in 2021, but endured quarterfinal exits in 2013 and 2015. Then, in March 2017, Enrique's Barca routed PSG 6-1 in the return leg of their last-16 match to make Champions League comeback history after losing 4-0.
PSG does not need a comeback of that magnitude but must improve.
“We pressed very high up the field and they tried to break our lines to find (striker Robert) Lewandowski. They did it very well and it caused us problems,” PSG captain Marquinhos said. “It's true that the small details make the difference. Conceding a goal from a corner, and allowing a second goal with the ball going in behind us. It's something we can't afford to do next week.”
Mbappé may need to play far better than he did in Wednesday's game, which went ahead with a reinforced security presence an alleged Islamic State terror threat against Champions League matches this week. Some armed police were stationed around the stadium but there were no incidents.
Achraf Hakimi's suspension forced Enrique into a reshuffle and he placed Marquinhos at right back. Surprisingly, midfielder Warren Zaïre-Emery was on the bench.
PSG made a bright start before the visitors took control.
Lewandowski's header from Gündogan's cross was cleared off the line by Nuno Gomes and, moments later, Raphinha's low drive drew a save from Donnarumma.
Donnarumma was at fault for the opening goal when he fisted Lamina's cross down the middle of the penalty area and was then stranded when Raphinha shot first time.
