Ben Close has been handed his improved deal as a reward for establishing himself in the Pompey first-team squad.
The 19-year-old midfielder missed out on a place in the match-day 18 in last week’s League Two win over Dagenham & Redbridge but then turned in a fine display in Wednesday’s Capital One Cup success over Derby County.
After the club took up an option on his contract at the end of last season, boss Paul Cook has made a swift decision that the young Fratton-based talent deserved a better deal.
That has seen Close now signed up for an extra season, until the end of the 2016-17 campaign.
Cook said: ‘The lad has come in on a standard contract from the Academy but I do believe in rewarding lads quickly.
‘These lads are with the first team now. They are not making the numbers up.
‘Sometimes by looking after them a little bit – not massively rewarding them with stupid contracts – it just gives them a little bit more recognition of what they have achieved.
‘We all saw how he played against Derby and I’ve seen how he conducts himself around the club.
‘Ben is a fantastic young player.’
Cook admitted it has been a crazy first week of the season for the teenager.
He said: ‘Ben wasn’t able to get on our bench last Saturday and probably left the ground disappointed.
‘But four days later he was feeling on top of the world.
‘That’s four days of football for you.’