The signing of is set to shake up the Wests Tigers backline with the club's stockpile of outside men desperate to retain their spots in the starting side when the Canterbury star arrives.
Mbye was announced as the first of Canterbury's big-name departures on Tuesday. He has signed a four-year deal with the Tigers from next year and is expected to slot straight in at fullback, a position which has been shared between Corey Thompson, Tui Lolohea and David Nofoaluma in 2018.
The 24-year-old also offers cover for Luke Brooks and Josh Reynolds in the halves, where veteran Benji Marshall's future beyond 2018 uncertain.
Mbye's arrival will create a selection jigsaw for coach Ivan Cleary, who already has Thompson, Nofoaluma, Malakai Watene-Zelezniak and cult hero Mahe Fonua as options on the wing. Lolohea can also play out wide but prefers fullback or five-eighth.
Nofoaluma is signed up until 2021. Thompson, Lolohea and Fonua are signed until the end of next season, but Watene-Zelezniak is off contract this year.
"Now there's a lot of pressure. You've still got to be performing at your best, and with adding him to the squad it's going to be a challenge to all the outside backs," Nofoaluma said.
"It's a good thing for the team and for the club. The best player deserves to play every week.
"I'm excited. He's an x-factor player, as you can see. He's been performing. Personally, I think this has been his best year that he's been playing at the Bulldogs. He did struggle a bit at the Dogs finding a position to play in, and I think for any player, every time when you change from position to position it's tough because you don't know where you're playing.
"For him to finally find a spot for himself at fullback, he's got a lot of confidence in his ability and it's showing throughout the first half of the year.
"It's a bonus for us to sign him to our club. I'm looking forward to seeing him here and bringing what he's got." Canterbury junior Mbye still had two years beyond 2018 to run on a heavily back-ended contract at the Bulldogs but will be squeezed out to free up room in a bulging salary cap.
Ex-Tiger Aaron Woods is also facing an uncertain future despite being just halfway through his first season of a four-year deal, but a fairytale return to his old club is unlikely given the dollars he would command and the club's strength in the front row. Russell Packer and Ben Matulino have had superb seasons since signing from St George Illawarra and the New Zealand Warriors respectively.
The Tigers clash with an under-manned Sydney Roosters on Sunday at Allianz Stadium looking to build on their round one win over the preseason fancies and last weekend's come-from-behind triumph over the Bulldogs.
Wests are at full strength and unaffected by State Of Origin selections, but the Roosters will be missing fullback James Tedesco, centre Latrell Mitchell, captain Boyd Cordner and fiery prop Dylan Napa.
"They've still got quality players in Cooper Cronk and Luke Keary," Nofoaluma said. "Halves are very important, and to still have that combo in the team this week it's still going to be challenging."
"I'm definitely not going to take this game for granted, we're still going to put in a quality performance and do our best to get the win.
"After round one, I think they're ready for a bit of revenge. There's no excuses for us to not put in a good performance, but we've still got to come and play plenty of our footy and the structure that we've been working on.
"We don't want to take any team lightly through this period. We definitely need the points and the wins coming in the back end of the year to make the finals."
James Buckley writes on AFL for The Sydney Morning Herald.
Most Viewed in Sport
Morning & Afternoon Newsletter