Tom Naylor insists that Pompey cannot afford to dwell on their recent habit of conceding late goals.
Opponents have struck in the closing stages on the past three weekends to deny the Blues valuable League One points.
Oxford were the latest benefactors, with Matty Taylor’s header on 90 minutes seeing the in-form side leave Fratton Park with a draw.
But with Southend visiting the south coast this evening, Naylor knows the Blues have to focus on getting things right.
Pompey’s skipper said: “We came into the dressing room after the game on Saturday and it felt more like a defeat. It was so frustrating.
“So we need to stop the rot of conceding late goals and everyone has to take responsibility for making that happen.
"You spend some time with the family on Sunday and try to forget what happened, but it’s there in your mind and it’s not nice."
“We’ve been playing really well and our counter-attacking has been brilliant, so it’s deflating when you don’t win.
“When you look at the points we should have collected from the past six or seven games, then we should be right up there.
“You spend some time with the family on Sunday and try to forget what happened, but it’s there in your mind and it’s not nice.
“So it’s useful to have another game on Tuesday bounce back and turn things around. It’s a big one for us and we’re ready to go again.
“I think everyone knows what we need to do. I’m the captain, but there are plenty of experienced guys in the dressing room and that can help.”
Pompey suffered play-off heartache last season and Naylor is confident that they can still secure a top-six finish.
He said: “We’re not ideally placed in the table at the moment, but there are a lot of games to go and plenty of points to play for.
“If we can get a run going, then you don’t know what can happen. We’re still positive about achieving something good this season.”