The loss, which was Valladolid's 14th of the season, kept the club in 19th position in the table, three points from safety.
"We have to be honest and admit that we didn't rise to the occasion. I haven't got any excuses for what happened here. This is not the way we want to play," he told reporters.
"We've had talks in the dressing room, but that's all I'll say. My job now is to help the lads recover psychologically.
"I thought we did okay for the first 20 minutes, but the game lasts 90. Their third goal was the last straw for me – that's not what professionals should be playing like."
Next up for Valladolid is a home match against Espanyol.