Cardiff Blues head coach Danny Wilson described aspects of his side's 26-15 Pro12 defeat by Zebre as "diabolical" and "embarrassing".
The Welsh side conceded four tries having beaten their Italian opponents 61-13 on 6 September.
Blues have since played five away games and lost them all, culminating in defeat in Parma.
"We can't hide away from the fact that the first half was embarrassing," Wilson told Blues' website.
"It was a performance where our defence was diabolical. There were one-on-one missed tackles that cost us dearly.
"When we attacked, we picked some poor options, and went out the back too early playing against a line-speed blitz defence that made us cough the ball up a few times.
"We had so much to do and in the second half we got ourselves back into the game and then failed to finish.
"The end of the game was all them again.
"I've used the word embarrassing for the performance and it is just that."
Wilson took over in June after a turbulent season, during which New Zealander Mark Hammett left after six months in charge and assistants Paul John and Dale McIntosh were left to see out the campaign.
Hammett had been appointed after Phil Davies, who coached Namibia at the 2015 World Cup, resigned in March 2014.
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Ex-Scarlets and Bristol assistant coach Wilson said he was left questioning his players' "attitude" for the first time since taking over.
"This is the first time since I have been here that the attitude was poor and we got what we deserved," he said.
"This is a tough place to come. Zebre played some good rugby and deserved the win."
Blues had to play the five consecutive away games because their home venue was used as a 2015 World Cup fanzone while games were staged in the Welsh capital.
The Welsh region host title-holders Glasgow on Saturday, 7 November and Wilson expects a significant improvement.
"I expect the attitude to be better next week because our attitude to the first half here was poor," he said.
Wilson added: "We are craving a home game because this is our fifth game on the road - but that is no excuse for that performance.
"I have been relatively positive about the performances; but this one I cannot be positive about and we need to put it right."
Scrum-half Lloyd Williams led the return of Blues' Wales World Cup contingent as he came off the bench in Parma.
Sam Warburton, Gethin Jenkins and Alex Cuthbert could be back to face Glasgow.