Richard Hughes and Michael Brown could cost Pompey another £175,000 after their contracts expire.
As it stands, Hughes and Brown’s existing deals end on June 30 and the duo have been informed they are not being retained.
Yet, under clause 19.2 of the FA rulebook, footballers are entitled to receive up to a month’s severance pay after their deals expire, if they can’t find an alternative club.
It means that if there are no takers for the midfield pair, Pompey will have to keep paying the duo until the end of July.
Brown and Hughes have already been paid around £900,000 between them since the turn of the year, without kicking a ball.
The pair have been sidelined ever since it emerged they would receive new deals at their existing wage levels upon reaching a set amount of games.
This was in line with contracts they signed several years before when Peter Storrie was chief executive at Fratton Park.
Both wanted to keep on playing for the club and offered to renegotiate their extensions, effectively volunteering pay cuts.
However, Pompey decided they could not afford any such contracts, refused to negotiate and stopped them from playing altogether.
The duo, however, continued to train and watch home matches.
Brown’s last appearance was in the 1-1 Boxing Day draw with Millwall at Fratton Park.
As for Hughes, his final game was in the 3-3 draw at Leeds days later, a match in which he scored his maiden league goal for the Blues.
Brown has been linked with newly-promoted Premier League side QPR, while Hughes has been consistently linked with League One outfit Bournemouth.