Javier Camuñas put the Navarrans in front in the 11th minute when he headed home from Walter Pandiani's cross, but Depor fought level just four minutes later as Riki blasted home from the top of the area.
Pandiani, though, restored Osasuna's advantage in the 24th minute with a header of his own, and Juanfran made it 3-1 eight minutes later when he slotted home after a low cross by Carlos Aranda.
Depor looked deflated from that point forward, and it always seemed more like Osasuna would score the next goal, though Albert Lopo did hit the post in the second half for the Galicians.
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