Neymar ends Barcelona hoodoo

Barca confirmed after the first leg of the quarter-final tie that the midfielder had suffered the problem to his left calf and will now undergo medical tests.

Iniesta, 32, had been replaced by Andre Gomes at half-time, the latest blow in a season that has been interrupted by two knee injuries.

The match itself saw Luis Enrique's holders win 1-0, ending their curse at the Anoeta with a first win in nine attempts courtesy of Neymar's first-half penalty, delighting Sergio Busquets.

"The team did themselves proud," Busquests said after the game.

"However, the tie is still to be decided. They [Real Sociead] are a good team."

The two teams play in the second leg at Camp Nou next Friday (AEDT), with Barcelona continuing its bid for a third straight Copa crown.