Lucas Alcaraz says Granada were second best to every ball in their 4-0 loss to Eibar on Monday night.
Adrian opened the scoring at the Estadio Municipal de Ipurua after 11 minutes from the penalty spot, in what was a contentious decision.
Sergi Enrich then added a second five minutes before the break, with further goals from Ramis and Pedro Leon.
After the game, a disappointed Alcaraz told the club's website that he couldn't quite account for such a below-par performance.
He said: "It's difficult to make an assessment of this game.
"I could talk about the penalty decision, which I don't believe should have been given.
"After that we could talk about the way the game developed, looking at how we've lost every duel, and there's not really much we can say about that.
"It hasn't been a good day and we owe our fans an apology."
He added: "When there was so much enthusiasm ahead of the game, given the favourable results elsewhere and the game we came here to play, we can't leave here at all satisfied, neither with the result or the image we've shown.
"We haven't had a problem when it comes to interpreting the game. Our problem was that we didn't win 80% of the duels: Individual duels, challenges, rebounds, pressing for the ball, dominating any areas…"