Sporting Gijon's English forward Nick Blackman came off the bench to score the winner as the Spanish second-tier side beat floundering Valencia 2-1 in the first leg of their Copa del Rey last 16 tie on Tuesday.
Blackman, on loan from Derby County, had been on the pitch for under 60 seconds when he headed home from close range after Valencia had failed to properly clear a corner, giving Sporting a famous victory at their Molinon ground.
Sporting, the club where Valencia coach Marcelino began his playing career and spent two years as manager, took the lead in the 35th minute through left back Javi Noblejas.
The visitors levelled on the stroke of halftime with a long-range strike from Dani Parejo which bounced over the line after striking the crossbar, with the goal being awarded after the referee consulted the video technology (VAR).
Valencia, who are 12th in La Liga with coach Marcelino under increasing pressure, have the opportunity to turn the tie around in next Tuesday's second leg at their Mestalla stadium.