Pompey did not compete in Robins loss - Mousinho
Portsmouth boss John Mousinho said his side "went under" after going a goal down in the 3-0 away defeat against Bristol City.
Anis Mehmeti scored City's opener on 20 minutes and two further goals in three minutes just after the half-hour mark all but secured the points.
"It was a really poor result and performance," Mousinho told BBC Radio Solent. "It's disappointing to follow up what have been really positive performances in the past couple of games.
"It was probably our best performance of the season against Coventry [4-1 win] and we were unlucky against Watford [2-1 defeat] on Thursday.
"One of the most frustrating things is we started the game OK and were the better side for the first 10-15 minutes. We really shot ourselves in the foot with the first goal. I can live with going a goal down but we went under after that. We didn't look like we competed.
"We tried to freshen things up after the busy period and with a game on Wednesday. Making those changes was our way of trying to have more energy but I don't think the changes were the issue. If you are not 'at it', then you get punished."