Trailing by a single goal at half-time on Wednesday, Barcelona manager Hans Flick introduced Gavi for Pedri at the start of the second half.
The hosts ultimately lost 2–0 at Camp Nou, leaving them with a challenging task to reach the semi-finals.
The second leg is set for next Tuesday at the Metropolitano Stadium, where the winner will advance to face the Arsenal–Sporting Lisbon victor in the semi-finals.
Catalan daily Mundo Deportivo explained the move, reporting that Flick substituted Pedri at the break because of hamstring pain.
The report added that the midfielder had looked below par in the first half, so, given his injury history, the medical staff advised against taking any risks by keeping him on the pitch.
The playmaker will now undergo tests to assess his availability for Saturday’s derby against Espanyol.
The same report adds that Frenkie de Jong could return from a six-week injury lay-off in time for the derby.
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