There was a healthy number of fans who made their way up to Burton from the south coast.
And skipper Lee Brown admitted that Pompey let them down with their performance at the Pirelli Stadium.
Reeco Hackett-Fairchild’s free-kick proved no more than a consolation after earlier goals from Tom O’Connor and Daniel Jebbison.
It stretched the Blues’ winless run to eight games in all competitions and Brown knows that is unacceptable
The defender said: “The number of points that we’ve picked up in the past few games simply isn’t good enough.
“All the boys know that, so now we’ve just got to get the shutters down and start to find some solutions pretty quickly.
"A lot of people have travelled a long way on a Tuesday night and have to go to work in the morning – we’ve let them down."
“This run of form we’ve been on lately is a real reality check for us and so we have to come out fighting.
“There have been some positive aspects to our performances in the past three games, but we’ve still come away with just two points.
“When you’re playing for this football club, we know you have to be doing better than that. That’s all there is to it.
“Our defensive record was good at the start of the season, but now we’re conceding two goals a game, so that has to improve.
“There are times when it can be hard to put your finger on why things go wrong, but the intensity certainly wasn’t there.
“A lot of people have travelled a long way on a Tuesday night and have to go to work in the morning – we’ve let them down.
“It will be a test of character for us on Saturday because people will soon realise what Fratton can be like if we play that way again.”