Instead it fell to Bono to get Julen Lopetegui's side out of jail, the keeper showing composure to side-foot home a low cross from Jules Kounde after a goalmouth scramble following a corner, becoming the first keeper to score in open play in La Liga in more than a decade.
Valladolid would have climbed to 14th with a victory but instead stayed 16th, four points clear of the relegation zone.
"It's incredible, it's difficult to describe and I didn't know how to celebrate," said the Moroccan.
"You do your job in your own goal and it's very strange to see yourself up in the other box."
The last keeper to score in open play in the league was Deportivo La Coruna's Dani Aranzubia, who struck to force a 1-1 draw against Almeria in February 2011.
Bono added: "Two years ago when I was at Girona I almost scored. I was reminded of that today and I looked at the dugout and the boss told me to get up there. The ball just fell to me, I did what I did and I'm very grateful."