Barnsley boss Paul Heckingbottom felt that frailties were exposed in the Reds' defence following this afternoon's loss at Ashton Gate.
Alex Mowatt and George Moncur were on target for the Reds, but goals from Tammy Abraham, Jamie Paterson and Aden Flint helped the Robins to victory.
On the result, the Head Coach said: "Today's second half has highlighted the things that we talk about with the players behind closed doors, our two centre-backs have really been holding the back four together at times and to lose one of them exposes other people's frailties and giving goals away.
"The players know they have to be better but they've been having to be better in every one of their games. Today everyone has seen their weaknesses first hand and why we badger them because moments like that, and it was schoolboy defending, not just for the goals, but the whole second half."
An injury to Marc Roberts was a major blow to the Reds' chances with the skipper replaced at the interval by Callum Evans after rolling his ankle in first half stoppage time.
Despite the Reds having to make a reshuffle in defence, Hecky insisted there is more than just the defence that can determine the outcome of a game.
"It's similar to when Yids got injured against Sheffield Wednesday, you're planning for every scenario and we knew we'd be exposed if a centre-back went off with Jacko' out injured and we got exposed massively.
"I'm singling them out but they know they didn't defend well enough and it was a real poor showing from the three full backs on the pitch but they also didn't get much help from the players in front whereas they did in the first half.
"It's always a team game, we win and lose together and again, when you're always pushing and pushing and why you want a perfect performance, it's for moments like that, now they can see why it is important.
"Even though we played well first half and dominated the ball and had the better chances, I still felt we needed more and we could have got more. Deep down we knew we'd need more goals but you're relying on Gethin playing out of position and for the players to stand up and do everything correctly and we didn't do that." he added.
Moncur has repaid Heckingbottom's faith by scoring a stunner in the second half, but there remains some debate as to whether or not the first goal is his or Alex Mowatt's. The work Moncur has shown off the field means he warrants his success, but added there is still plenty he can do to improve his game.
"The credit I can pay George is the things we've been asking him to do in training and driving about he's been trying to do it. It's pointless breaking from midfield to pass back or square, we encourage the end product and to get your shots in.
"He did it in the last match and was unlucky, he's done it today and got the rewards but I spoke to George about his work off the ball. As a squad we've not got many natural defenders and we have to work really hard if the players want to be in the team, the team is about winning, we're about more than just playing pretty football." added Hecky.
Reds midfielder Matty James missed out today as his partner gave birth to their first child early on this morning and expressed his delight at the midfielder becoming a father for the first time.
"Matty's wife has had a baby boy first thing this morning, he made it there just in time, with 13 minutes to spare. We're all chuffed for him and it would have been nice to get the win for him but we couldn't have everything today."
Nearly 700 Reds fans made the long journey down to Ashton Gate and Heckingbottom was gutted he could not send them home with something to cheer.
He said: "You could hear the fans all game, I feel for them because them as well as the players, we shouldn't have lost that game. We've given them three goals, Bristol will be delighted but we've given them three goals and an unfortunate injury has cost us really."