Andy Awford has vowed to tighten up Pompey’s defence ahead of their season finale.
The Blues clinched an improbable 4-4 draw at Bury at the weekend with two goals in the final three minutes to level matters.
On the flip side, the visitors were highly vulnerable themselves at the back throughout the Gigg Lane fixture.
Striker Hallam Hope and left-winger Danny Mayor wreaked havoc over the 90 minutes for a defence containing recalled duo Ben Chorley and Bondz N’Gala.
Danny East and Nicky Shorey also made up a back line that included three changes to the one who kept a clean sheet at Northampton the previous match.
This Saturday, Plymouth visit Fratton Park for the last match of the League Two campaign.
And in the build-up Awford will be seeking to address the defensive weaknesses which appeared at Bury.
He said: ‘Overall, we’re delighted with the Bury result.
‘But I am disappointed with some aspects of the first half and I’ve told the players that.
‘The first half wasn’t right – we won’t sweep it under the carpet, that isn’t right.
‘We’ll have to watch it, address it and deal with it and that’s what we’ll do.
‘I’ll speak to them individually and then as a group. We’ll work on some things this week in training to make sure we are not that way again in the first half against Plymouth.
‘And, hopefully, we can still see the attacking stuff come out in us.’
The Bury game represented Chorley’s first appearance in seven matches – an absence largely influenced by suspension.
Joe Devera and Sonny Bradley – who started against Northampton – were on the bench alongside Jack Whatmough.