Coach Ian Chandler insists Portsmouth must cut out their ‘showboating’ and show killer instinct as they welcome Guildford to Rugby Camp in London two south west.
The city club have suffered in the opening month of the season from their inability to close out games.
They have got themselves into good positions on a number of occasions, only to come away with nothing and that has been disappointing.
After last season’s relegation, Chandler was optimistic his team could bounce straight back up.
But that promotion aspiration has been derailed slightly by three defeats on the bounce.
Confidence has also taken a knock and the pressure is now on as Portsmouth battle to get back into the race at the top of the table.
Chandler knows his side can’t afford too many more defeats if they are to have any chance of mounting a challenge.
Fourth-placed Guildford will also present a big obstacle to those hopes.
‘This is a game we really need to win,’ said Chandler.
‘We can’t afford to fall too far behind and get cut adrift from the top teams.’
Portsmouth can take heart from their 53-15 dismantling of Southampton University in the Hampshire Cup last weekend.
Dan Sargeant ran in a hat-trick of tries as the team showed a far more clinical touch.
Chandler added: ‘Last weekend we showed in the Hampshire Cup win over Southampton University that we can play disciplined rugby when the league pressures are off.
‘I would say the University side were better than two of the teams that have beaten us in the league.
‘We must learn to play pressure league rugby and turn the screw when we are on top.
‘At times we have tried to play rugby in the wrong areas of the pitch and have been punished for it.
‘Less showboating and a greater clinical approach is needed.
‘At the moment we are falling between two stools.
‘First and foremost, if we start to play well the results will take care of themselves.
‘We must stop trying to force the games and make better decisions.’
Curtis Barnes returns at full-back, with forwards Harry Cripps and Jason Crabb back in the squad.
Apart from those changes, Chandler keeps faith with the players who did so well in the comprehensive cup win over the students.
Portsmouth: Barnes C, Duffus A, Carpenter, Chandler, Gee, Barnes A, Duffus C, Hankey, Houlihan, Sargeant, Farmer, Crabb D, Crabb J, Foukes, Richardson. Richards G, Cripps, Rassat