Watford boss Tom Cleverley admitted his side failed to reach the standards they produced against Portsmouth on Boxing Day as defeat by Cardiff City ended their unbeaten home record for the season.
"All good things come to an end. Today we let them off the hook too many times with sloppiness, with lack of concentration, and it was a game we have to take on the chin and say that we weren't good enough to a man," Cleverley told BBC Three Counties Radio.
"As a defensive unit, if we're going to go from a three to a four, or a five to a four, however you want to call it, we have to become high-urgency defenders where conceding a goal has to be the worst possible thing that can happen to you.