The Gills will be in line to receive some money for Tucker this summer due to the fact that the defender is under the age of 24.
It is understood that the club will be willing to avoid a tribunal if they receive £300,000 for the 22-year-old.
The centre-back’s current contract at Gillingham is set to expire in June.
Whereas Portsmouth are believed to be in the market for a new centre-back this summer, they are not willing to match Gillingham’s demands.
Despite the fact that he was able to show some signs of promise in the third-tier last season, the centre-back was unable to prevent his side from suffering relegation to League Two.
Gillingham were consigned to this fate on the final day of the regular campaign as they were beaten 2-0 by Rotherham United.
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With a move for Tucker seemingly no longer on the cards at Portsmouth, it will be interesting to see who they opt to switch their attention to in the coming weeks.
When you consider that the defender managed to record a respectable average WhoScored match rating of 6.78 in the third-tier last season, it wouldn’t be a shock if another team in this division decides to make a move for him.
Pompey’s search for a new centre-back may be impacted by Sean Raggett’s decision regarding his future at Fratton Park.