The premiership-winning mentor will join Paul McGregor's staff as an assistant on a one-year deal.

The signing comes just a year after Flanagan was banned by the NRL for engaging with the Sharks during his one-year suspension in 2014, with Todd Greenberg announcing in September the coach will be free to return to the game from December 18.

Flanagan remains banned from taking a head coaching role for the next two seasons.

The signing comes after the Dragons overhauled their coaching staff earlier this month in a bid to produce an immediate turnaround on the field following a disappointing season.

McGregor kept his job, despite the side finishing 15^th on the ladder, with Flanagan's former Sharks colleague James Shepherd also joining the club as an assistant.

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Dean Young retained his position, with Ben Hornby departing, while the club also confirmed Wednesday Matthew Head will remain as Canterbury Cup coach.

Faced with the opportunity to work with a premiership-winning coach, McGregor said he looks forward to working with Flanagan.

"Shane will be a valuable asset to the Dragons' endeavours in 2020," McGregor said. "His success has been proven time and time again over many years and we're glad to have him on board."

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