"We're going to need a lot of things to go for us to get into the play-off picture now," said Coleman to the media after the game.
"I think the performance was a bit of a hangover from our FA Cup run. It was a good time for Bristol to play us after all the effort and emotion that went into the Chelsea match.
"I thought we started okay, but I was always worried we might run out of steam. The big disappointment was the goals we conceded.
"The first was from a set-piece, and the second stemmed directly from our own set-piece, which was just as bad.
"I think the players gave everything, but it's difficult enough to come here at the best of times, let alone on the back of a huge cup tie."