Stand-in manager Neil McDonald blamed defensive mistakes for Wednesday's 3-0 defeat at Fulham.
McDonald, who is in charge of first-team affairs at Ewood Park while Sam Allardyce undergoes a heart operation, admitted he was surprised at the full-time scoreline from the Craven Cottage clash.
The defeat ended a run of two consecutive victories for a resurgent Rovers side.
"I thought the first half was played some really good stuff," said the interim manager.
"We should have scored in the first minute but we didn't take that chance. Then there was some poor defending for the three goals all in all.
"The only chance they had in the first half they stuck into the back of the net.
"They were a bit more clinical than we were and that's why they went in front at half-time.
"Second half, from our point of view, we huffed and puffed a bit, but there was no real end product and we are all disappointed with the way that they scored the other couple of goals."