Hawthorn sign club chief executive Justin Reeves' 209cm son, Ned Reeves, as part of the new pre-season supplemental selection period.

The 20-year-old big man began training with the Hawks straight after Christmas before stopping a fortnight ago, as per AFL rules. Hawthorn had a spot open because of premiership player Will Langford's retirement.

"I'm stoked at the moment it's a dream come true," Reeves said.

"(I will) hopefully try to be a bit like (teammate Jon) Ceglar, so mainly play in the ruck, hopefully go well there, then be able to push down forward and kick some goals."