Lionel Messi came off the bench at half-time to score twice as Barcelona defeated 10-man Real Betis 5-2 at the Camp Nou on Saturday.
Ousmane Dembele had given the home side the lead after 22 minutes, before Antoine Griezmann's penalty was saved and Antonio Sanabria equalised in first-half stoppage time.
Messi, though, made an instant impact as his clever stepover set up Griezmann five minutes after the restart and he then converted a penalty after Aissa Mandi was shown a red card for handball on the line following VAR review.
Loren Moron set up a tense final 15 minutes, but Messi settled matters with another late third goal and Pedri added a fifth as Ronald Koeman's side closed out a much-needed La Liga victory.
Barcelona went in front after 22 minutes when Dembele collected a ball from Griezmann on the right before cutting back inside to fire a left-footed shot past Claudio Bravo and into the top corner.
After Griezmann hit the post, Barcelona were awarded a penalty in the 32nd minute when Fati was bundled over, only for the French striker to see his spot-kick saved.
Real Betis equalised in first-half stoppage time when Sanabria slotted the ball in after Cristian Tello's cross from the left was not cleared. Messi replaced teenager Fati for the second half, and made an instant impact to set up Griezmann in the 49th minute.
Jordi Alba sent a cross in from the left, which Messi jumped over to let the ball run to an unmarked Griezmann, who tapped in.
As the hour mark passed, Betis found themselves down to 10 men following a VAR review of handball.
Messi took the ball around the goalkeeper and cut a pass back for Dembele, whose shot was blocked on the line by Mandi.
The incident was reviewed by VAR, with the referee deciding it was handball and showing Mandi a red card.
Messi made no mistake from the penalty spot, drilling the ball into the top corner, to give Barcelona some breathing space.
Betis set up a hectic final 15 minutes when Loren slotted home from 10 yards, but Messi wrapped things up in the 82nd minute after a one-two with Sergi Roberto.
The Argentinian playmaker was denied his hat-trick by an offside flag before midfielder Pedri added a fifth in stoppage time – the teenager's first goal in LaLiga.