Parker, who faces Briton Joyce at the AO Arena in Manchester on 24 September, was a training partner for Fury amid the “Gypsy King”’s preparations for a WBC title defence against Dillian Whyte in April.
Fury stopped fellow Briton Whyte in Round 6 to retain the belt and remain unbeaten, and the 33-year-old is now returning Parker’s favour by helping the Kiwi ahead of his fight with Joyce.
“Team back together and ready for camp,” Parker wrote on Instagram, in a caption to a story video of himself and Fury sat ringside in a gym.
“It’s go time, let’s go!” Fury shouts in the video.
Fury has claimed to be retired since knocking out Whyte, but the 33-year-old has gone back and forth on the matter, and The Independent reported last week that the WBC champion is in talks to fight Derek Chisora this December. Fury has twice beaten Chisora, outpointing his compatriot in 2011 and stopping him in 2014.
Many fans are keen to see Fury take on the winner of Anthony Joshua’s rematch with Oleksandr Usyk, which takes place on 20 August.
Joshua is out to regain the WBA, WBO, IBF and IBO heavyweight titles from the unbeaten Ukrainian, who beat the Briton via decision last year.
The winner of that rematch could then face Fury to crown an undisputed champion, as long as Fury has not lost or relinquished the WBC belt by then.