Christian Burgess bemoaned the pain of another late goal hurting Pompey.
But the defender denied the Blues have a psychological barrier stopping them seeing out games.
Paul Cook’s side saw three points turn into one with Ollie Watkins’ 90th-minute leveller earning Exeter City a 1-1 draw.
The goal was the fourth late effort Pompey have conceded in the past seven games.
It was a frustrating and painful moment with it looking for all the world it would be back-to-back league wins.
Cook and his team were left searching for the reasons why they are failing to see out games for a clean sheet.
It’s now 11 matches since they did that against Crawley at the start of January.
Burgess was hurting like the rest of the team and nearly 700 travelling fans – but dismissed it’s a mental issue for Pompey.
He said: ‘We need to start winning games like this and putting pressure on teams above us.
‘We have to believe in ourselves.
‘It’s massively disappointing. Three points were up for grabs.
‘But it’s not psychological conceding late.
‘Jayden (Stockley) could have scored in the first half for them.
‘I felt we should have had a penalty at the end.
‘They are going to pile the pressure on and throw people forward.
‘It’s not psychological because there are different circumstances. I just think it’s one of those things at the minute.
‘It wasn’t comfortable, but you’ve got to stay focused.
‘They got a lucky little ricochet and from there he’s squirmed it in.
‘It’s one of those things.
‘They played pretty well, made a few subs and threw a few men forward.
‘It’s just one of those things. It’s not happening at the minute but we have to believe we will turn the tide.’
Cook spoke of continuing a no-nonsense approach against Paul Tisdale’s side, after grafting their way to a 2-1 win over Cambridge United on Saturday.
That’s exactly what Pompey did –and it looked like they were going to be rewarded with an impetus-injecting victory.
Conor Chaplin got his ninth goal of the season and could have added two more in the first half.
The Blues were more direct in their play and Burgess can see why a more rugged style is being implemented.
He said: ‘The pitches are churning up, it’s a midweek away game and teams are tough to play against.
‘We’ve set up to be tough to beat and did that pretty well. We did the same against Cambridge.
‘If we hold out it’s a fantastic 1-0 win and we leave happy. But we have to go to Stevenage and keep believing.’