Portsmouth edged hosts KCS Old Boys 15-14 in an ugly London two south west encounter.
The home side had two players sent off as errors punctuated the contest.
‘We were by far the better side but kept giving them hope through our errors,’ said Portsmouth coach Ian Chandler.
‘It was important that we rediscovered the winning formula.
‘We have now got three consecutive home games ahead of an end of season cup final.
‘A number of players are coming back from injury so they are all playing for their places in the cup final team.’
Portsmouth dominated the opening 15 minutes and prop forward Dan Sargent emerged from a catch and drive at a line-out to claim his 24th league try of the season.
But the Rugby Camp side handed KCS two scores and went in 14-5 down at the break.
In the second half, KCS resorted to giving away a string of penalties as Portsmouth turned the screw.
A penalty try converted by Andy Barnes, who also kicked a difficult penalty, saw Portsmouth home.
A strong second-half performance was key to a 25-19 bonus-point win for United Services at Southampton in Hampshire one.
Outside-half Matt Davis produced a match-winning display after Services trailed 14-13 at the break.
Services went behind but responded with tries from full-back James McAvoy and hooker Dave Reed.
Just before the half finished Southampton mauled their way over again from a five-metre scrum.
In the second half, Davis stepped up to the plate and opened up the Southampton defence at every opportunity after the break.
Davis scored one try and provided another for winger Alex Doolan but the home side scored forward try two minutes from time.
Services, however, closed the game out to finish the contest.
‘With such a young side this is the highlight of the season for me,’ said match-winner Davis.
‘To put in a performance like that and come away with a bonus win is a credit to the side and how far the club has moved on.
‘I really enjoyed it and that is what this club is about.’
Southsea Nomads were beaten 41-10 by Locks Heath Pumas in Hampshire two.
Ben Smith scored a penalty and conversion and James Hardy recorded a try for Nomads.