Athletic Bilbao wasted its chance to regain the Spanish league lead when it lost 1-0 to Valencia on Saturday.
Denís Cheryshev scored for Valencia, which ended a three-game winless streak and moved to ninth place.
Athletic stayed fourth, two points behind leader Real Madrid which hosts third-place Atlético Madrid later Saturday in the first capital derby of the season.
Athletic and Real Madrid were the only unbeaten teams in the league entering the weekend. Athletic hadn't lost at home in 14 consecutive matches
Cheryshev scored from close range after a fast breakaway in the 27th minute at San Mamés Stadium.
"I liked how the players responded," Valencia coach Albert Celades said. "We were coming off a sequence of very difficult matches. They put in a great effort."
Valencia had conceded nine goals in its previous three league matches.
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