Already signed for 2012, the two youngsters have inked three-year extensions on their deals, a commitment that binds them to the Broncos until the end of the 2015 NRL season.
McGuire has been touted as a future international after making the Kangaroos train-on squad, while Hoffman was a certainty to represent New Zealand if not for ill-timed injury.
Coach Anthony Griffin said the pair had earned their re-signing and formed an important part of the Broncos’ squad into the future.
“Both of these players were identified by the Broncos as having great potential and have been in our system for a long time,” said Griffin.
“We are pleased they have agreed to be part of the Broncos for the long term – four more years is a strong commitment.
“This is the first stage of our process of keeping our current group together and continuing to develop the talent we have brought through the Broncos’ system.”