The forward completed a deadline-day loan switch to Fratton Park from Wolves until January.
It's the second time the 27-year-old has linked up with JackettÂ after being signed by him for Â£3m when he was in charge at Molineux.Â
Mason, who made his Pompey debut in the 4-0 Checkatrade Trophy win over Gillingham on Tuesday, knows his manager has belief in his ability.
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And the ex-Cardiff talent isÂ looking to repay that faith.
'˜He just knows who I am as a player,' Mason said.Â
'˜He tried signing me a few times when I was at Cardiff and showed that belief in me back then. It was a shame when I did go to Wolves he left quite soon afterwards.
'˜But during that short period I got the feeling he believed in my ability.
'˜He showed good faith in me back then.
'˜I feel like the relationship would have blossomed (if Jackett had remained as manager).'
Mason drops down to League One after spending the majority of his career in the Championship.
He's only had one full campaign in the third tier during the 2010-11 season for Plymouth.
Mason netted seven goals from 37 appearances, earning him a switch to Cardiff.
Although he knows he mustÂ acclimatise, he is confident he can be a goalscoring threat.
Mason added:Â '˜I had one season in League One when I was at Plymouth but that was a long time ago.
'˜That was in a team that struggled that season. We went down.Â
'˜I'll have to adjustÂ but I want to hit the ground running and get on this positive ride the team is on.'