Prop Matagi joined on a season-long loan from Huddersfield Giants for 2021 but injured his calf in pre-season training.
The ex-Kiwi international, 33, has missed the club’s opening eight games but has been passed fit to return in the Betfred Super League clash at Warrington Wolves tomorrow.
Coach Daryl Powell said: “He will play.
“I am looking forward to seeing him play, it’s been a while waiting for him to make his debut so I’m looking forward to it and I think he is as well.
“He has trained well so he’ll be on the bench.”
Asked what he expected of the former Parramatta Eels forward, Powell added: “He will need to get his game legs and lungs.
“Because obviously you can train as much as you want, but when you get out on the field it is a little bit different, the competitive nature of it.
"He has just got to get out there with the boys and enjoy it and he will grow from there."
With fellow props Grant Millington and Liam Watts out due to injury and suspension respectively, Castleford will be grateful of having someone of Matagi’s presence back in their ranks.
Powell said Tyla Hepi is also “back in the mix” as Tigers look to bounce back from Monday’s late defeat against Hull KR but half-back/full-back O’Brien is sidelined.
“He’s injured his calf and it’s a disappointing injury for Gaz,” said the coach.
“He’s a little bit down at the moment. He’s going to be out for a while.
“We’re not certain how long yet.”
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