Sevilla's Jules Kounde scored a fine goal and Ivan Rakitic struck against his old side as Barcelona lost their Copa del Rey semi-final first leg.
Kounde ran from his own penalty area, beat four Barca players and confidently fired past Marc-Andre ter Stegen.
Rakitic - who left the Nou Camp at the end of August after winning 11 trophies with Barca - made sure with a thumping finish into the roof of the net.
Lionel Messi could have snatched a late away goal but was denied by Bono.
Julen Lopetegui's side saw out the win without conceding to take a big advantage into the second leg at the Nou Camp on 3 March.
Barcelona beat Sevilla 5-0 in the final three years ago.