Dan Sargent bagged two tries to help Portsmouth pick up a 33-26 London two south west win at Old Alleynians.
The impressive prop forward has been in free-scoring form this season.
His two close-range efforts took his tally for the season to 11.
‘Dan spent a spell playing in New Zealand and has come back a very powerful player,’ said Portsmouth coach Ian Chandler.
‘He takes a lot of stopping from close in and isn’t far off becoming a very talented prop forward.’
Chandler was also pleased with the way his side fought back in the closing stages of the game to come from behind to win.
‘We won it at the death and usually it is other teams who do that to us,’ said Chandler.
Portsmouth started well with winger Danny Harris notching his first senior try before the home side hit back to lead 8-7 with a try and a penalty.
Right on half-time, Sargent bullied his way over for his first score to send Portsmouth into the break with a 14-8 lead.
The Rugby Camp club found themselves 19-14 in arrears in the second half.
But scrum-half Cameron Duffus put Portsmouth 21-19 ahead with 25 minutes remaining in an attractive contest.
By this stage it was a slog with the pitch cutting up badly.
And Old Alleynians took advantage when the ball stuck in the mud to regain the lead with a converted try.
‘In the past our heads would have gone down after that but you could see the determination in the players on the restart,’ said coach Chandler.
‘We refused to give up against a good Old Alleynians side who had some dangerous three-quarters.
‘To our credit we marshalled them well and snuffed out their main threat.’
Master poacher Sargent went over for his second try and Dan Neville gave the visitors a slender 28-26 lead going into the closing stages.
Richard Farmer sealed the win with a late try that sparked wild celebrations.
‘It sets us up nicely for our big game against Tottonians next weekend,’ said Chandler.