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Marc-Andre ter Stegen was beaten by Ivan Sanchez after just six minutes, but was in fine form after a seven-month absence.

Barcelona's lead at the top of LaLiga extended to seven points after second-half strikes from Raphinha and Fermin Lopez overturned the hosts' advantage.

Flick confirmed his fellow German would return to the sidelines as Barcelona prepare to visit Inter, who are level at 3-3 in the Champions League last four after a thrilling first leg last Wednesday.

"We'll see about Marc, he did well today, but Szczesny will play in the Champions League and against Real Madrid," Flick said.

Flick made nine changes in total for the trip to Valladolid, where his side extended its unbeaten league run to 15 games despite heavily rotating.

That is Barca's longest run in the competition since going as many games undefeated in April 2022, and Flick was pleased with what he saw from his backup options.

"I'm not disappointed. When you make that many changes, it's not easy for the players, they're young," he said.  "I believe in them. I have confidence. When there is a lot of rotation, the level is different.

"I was able to rest some players and give some minutes to others. It wasn't easy. There were a few mistakes, quick transitions, but [Ronald] Araujo and [Andreas] Christensen had a good game and Ter Stegen too."

Fermin was one of those to get the start from the off, rounding off a fine performance with a smart finish that proved to be the winner after an exchange with Gerard Martin.

The Barcelona attacking midfielder also created three chances, a total only bettered by team-mate Pedri, and Flick hinted Fermin may have done enough to earn a start in Milan.

"He is a player who always has a chance to start. He can play in different positions," the former Germany manager said.

"The goal is three points, and I'm satisfied that we got them. Mission accomplished."