A Round 20 NRL debutant, Matterson played in seven of Manly's final eight games this year, and while they all came off the bench, he impressed in both attack and defence.
The 25-year-old, who is on the older side of what is typically expected from NRL debutants, appears to have a future in the NRL, and the Sea Eagles confirmed they share that view with his contract extension.
The new deal means the second-rower means Matterson will be part of Manly's Top 30 until at least the end of the 2025 season.
While he is listed as a second-rower, he is also a genuine utility, able to play at centre, five-eighth or lock as well as on the edge, and it could see him raise a hand to become Manly's permanent number 14 next season.
Voted as Manly's Rookie of the Year at the recent club awards, he also won the NSW Cup feeder side - the Blacktown Workers Sea Eagles - player of the year.
“He showed in the seven NRL games he played that he can compete for a position in our 17 each week in 2024.
“Dean has a great attitude and he cares deeply about his rugby league. He is a mature player. It hasn't come easy for him, so it's great to see him get an opportunity.”