But Ennis is also adamant Raiders mentor Ricky Stuart can rebuild the Green Machine, admitting his relationship with the coach almost convinced him to move to Canberra for the 2015 season.

Ennis will play his first game for the Sharks when they take on the Raiders in Cronulla on Sunday night.

It marks a new start for the embattled club, which has been haunted by its involvement in the ASADA supplements scandal.

Skipper Paul Gallen has served a backdated, 12-month drugs ban and coach Shane Flanagan is also back after serving a one-year suspension.

But Ennis and former Bulldogs teammate Barba provide the fresh spark as marquee recruits in a mission to move forward.

"There's a great vibe around the club now," Ennis said.

"The guys got confidence out of performing in the [Auckland Nines] and the boys seem happy, especially the ones who have been here the last few years.

"They seem to be in a good place, I think everyone wants to hit the ground and get it underway with some footy."

Ennis was a key target in the Raiders' bold recruitment strategy last year, which also included James Tedesco and Kevin Proctor.

The former NSW State of Origin rake was given a tour of Canberra by Raiders chief executive Don Furner, with reports he was offered a two-year deal worth $500,000 per season.

But in the end, Ennis said family won out of any desire he had to reunite with Stuart.

"I've got four young children and it was the biggest and toughest decision in terms of contracts that I've faced in my career," Ennis said.

"It came down to family. I really liked everything that Canberra had to offer and the direction they're taking the club down there.

"I obviously get along with Ricky really well, but I've got young children in school [in Sydney] and I really feel like, after talking with [Flanagan], that the Sharks are going in the right direction.

"It's turned out to be a good move. I really liked what Ricky spoke to me about Canberra and they've got a good roster, but the right decision was for me to go to Cronulla."

The Raiders have remained tight-lipped about their round-one selections, with Stuart to settle on his line-up on Tuesday afternoon.

Mitch Cornish and Sam Williams are battling for the halfback spot, with Cornish tipped to get first crack in the No. 7 jersey.

Jack Wighton is expected to get a chance to prove himself at fullback, stepping in to fill the role formerly held by Anthony Milford and Josh Dugan.

The Sharks are also putting their faith in a new fullback, recruiting Barba after a failed stint at the Brisbane Broncos.

Barba was in career-best form when he played alongside Ennis at the Bulldogs in 2012. But after moving back to Sydney, Ennis believes Barba is set to get back to his devastating best.

"Ben's done everything he can to have a really good season and I'd be surprised if Wade Graham doesn't burst into representative football this year," Ennis said.

"I don't want to put too much pressure on the boy [Barba], but he's really enjoying his time down here and the signs have been good. Like me, he probably just wants to hit the ground running."

Ennis was wary of writing off the Raiders, despite two lean years.

"There's plenty of strike, there's no doubt about that. They're a very dangerous side and I always find them tough to play against."

NRL ROUND ONE

Sunday: Cronulla Sharks v Canberra Raiders at Cronulla, 6.30pm. TV time: Live on Fox Sports 1