St George Illawarra have sealed a three-year deal for Broncos veteran Andrew McCullough to join the club immediately.
After sitting out of Broncos training since Thursday, McCullough’s move was confirmed on Monday.
The 31-year-old former Queensland hooker has been targeted by new St George Illawarra coach Anthony Griffin for his "game-management skills".
The clubs have been negotiating around a McCullough move since the new year.
Two spots now remain in the Dragons' top 30 roster for the 2021 Telstra Premiership season following the signing of the 268-game veteran.
"It's no secret that we have been interested in Andrew McCullough for a while now and we're pleased to see him finally sign with the Dragons," general manager of football Ben Haran said.
Match Highlights: Sharks v Dragons
"Signing a player of Andrew's calibre will no doubt inject plenty of experience into our team and wider squad while his style of play will complement the development of the exciting young talent we have here at the Dragons."
McCullough and Dragons halfback Ben Hunt played together under Griffin at the Broncos, along with five-eighth Corey Norman, and the trio are set to fill the spine with Matt Dufty at fullback.
Griffin's plan was for Cameron McInnes to play lock - the position he will fill at Cronulla next season after recently agreeing to a four-year deal with the Sharks - but he tore his ACL at training on Friday and may not play at all this season.
McCullough returned to Brisbane over the summer after a short stint at Newcastle last year in which he impressed early, only to tear his hamstring off the bone and undergo a lengthy recovery.
The signing of McCullough, who was absent from Broncos training on Thursday, would enable Hunt to focus totally on playing halfback as St George Illawarra also have another specialist hooker, Billy Britain, in their squad.
McCullough had been jostling for a starting No.9 role at the Broncos with Jake Turpin.
Brisbane still have fellow veteran rake Issac Luke on a train and trial contract and also ex-Knights and Manly hooker Danny Levi as another option after he joined Intrust Super Cup club Norths Devils.
Luke was called into the Maori squad on the weekend for this Saturday's Harvey Norman All Stars in Townsville.
McCullough's exit frees up much-needed salary cap space as the Broncos work on keeping their best and brightest young talent beyond 2021 including Kotoni Staggs, Tom Dearden and Xavier Coates.
Broncos chief executive Paul White thanked McCullough for his efforts, having started in the club’s talent development system as a 13-year-old.
"Macca has always been well respected by his fellow players and staff, and favourite with our members and fans," White said.
"It is sad to see him depart Brisbane, but he will always have a special place here at the club.
"We wish Andrew and Carlie all the best in what will be a new and exciting opportunity for them."
This article contains content that is only available on NRL.com