MADRID — Dani Olmo celebrated his delayed Barcelona debut with a goal to seal a 2-1 comeback victory at Rayo Vallecano in La Liga on Tuesday.

The Spain playmaker's 82nd-minute strike helped Barcelona claim its third win from three matches, maintaining new coach Hansi Flick's winning start to the season.

Barca finally managed to register Olmo with La Liga after signing him from RB Leipzig earlier in the day, and he made an instant impact at Vallecas stadium when he came on at halftime.

Unai Lopez put Rayo ahead against a flat Barca in the first half, but Olmo's arrival energized the Catalans, who leveled through Pedri before the young debutant struck the winner.

" (I've been waiting to play) since I arrived, looking forward to the first game, the debut, and what better way (to mark it)," Olmo told DAZN.

"I was really looking forward to it, I felt physically ready to play, and it finally happened today.

"I am very happy to have made my debut and helped the team."

In the final stages, 17-year-old defensive midfielder Marc Bernal was taken off after appearing to twist his knee, leaving Flick worried about the youngster, who has impressed at the start of the season.

"It's a sad victory because Marc Bernal is injured, and it doesn't look so good," said the German coach.

"We have to wait until tomorrow to wait and see how bad it is.

"We win, it's OK, but when you see the dressing room nobody is happy."

Rayo Vallecano, celebrating its centenary year, signed former Real Madrid playmaker James Rodriguez earlier in the week, and he watched on from the presidential box as the capital club started strongly.

The host attacked with intent and got its reward when Jorge De Frutos drove forward on the right and crossed for Lopez, who finished with a low effort at the near post.

Rayo minimized Barcelona's threat in the first half, except for the odd occasion teenage star Lamine Yamal managed to work his magic.

Flick hooked Ferran Torres at halftime and threw on Olmo for his debut, after he had missed its first two league matches waiting for Barcelona to get its finances in order to complete his registration.

With Olmo entering the fray he took up a central attacking midfield position, with Brazil winger Raphinha restored to the left flank.

The former Barca academy player quickly began to make his mark on proceedings and the Catalans started to generate chances.

Polish veteran Robert Lewandowski should have leveled proceedings, but could not get a solid touch close to goal on Raphinha's dangerous cross.

Raphinha whistled a freekick narrowly wide and Olmo smashed a 30-yard drive against the crossbar.

Barca finally made the pressure count, and Pedri leveled on the hour, after exchanging passes with Raphinha, before sweeping the ball home.

'A good goal'

Barca thought it had got a second 10 minutes later, when Yamal's shot was saved, and Lewandowski worked room to tuck the rebound into the net.

However, the goal was controversially disallowed after a VAR referral when the referee deemed Jules Kounde guilty of a foul, when he made light contact with Pep Chavarria's foot in the build-up.

The visiting side did not lick its wounds for too long, continuing to pile on the pressure. It eventually paid off again, as Olmo finished a Yamal assist with aplomb.

"I'm always a player who looks to score, Lamine found me and I finished well, a good goal, I'm very happy," added Olmo.

Barcelona played with an energy in the second half that has often been missing late in games in recent years, with the team appearing notably fitter under Flick.

The victory guarantees Barca will top the table after the third round of matches, despite various injury issues affecting important players including Gavi, Frenkie de Jong and Ronald Araujo.

Bernal has started all three of Barcelona's games this season, and the club will hope he does not join the list of long-term absentees.

Champion Real Madrid visits Las Palmas on Thursday while Atletico Madrid hosts Espanyol on Wednesday, among other fixtures.

AFP