Coventry City manager Andy Thorn felt his side never got going in the 3-0 defeat to Ipswich Town on Monday night.
"We never got going and for 20 minutes we were still in the dressing room," said Thorn to the Press Association.
"Against good, experienced players you can't do that and they played really well in that period.
"Ipswich are the best side we've played this season but, having said that, that was our worst performance.
"We gave ourselves a mountain to climb and that was disappointing because one of our strengths has been winning early battles and weathering storms.
"Going into the game we had the best defensive record, in terms of goals conceded, and that made it even more frustrating.
"We were proud of that and are disappointed by the manner in which we've let it slip, but no individuals were to blame. It's a collective thing and we all contributed to our own downfall."