Blues coach Leon MacDonald opens up on plans for Roger Tuivasa-Sheck's playing position

Blues head coach Leon MacDonald isn't ready to pigeonhole NRL star Roger Tuivasa-Sheck into any position months out from his highly-anticipated cross-code switch.

Tuivasa-Sheck and the Blues confirmed on the eve of Super Rugby Aotearoa that the Warriors captain will make the move to the Auckland franchise on a two-year deal once his rugby league commitments have come to an end.

One of the highest-profile players to make the jump between the two sports, much speculation has centred on where Tuivasa-Sheck will play in the XV-man game.

A fullback who can cover wing in league, the 2018 Dally M Medallist has been touted as a potential fullback, wing or midfielder in union.

In his last stint as a union player for the Otahuhu College 1st XV, Blues U18 and New Zealand Schools sides in 2011, Tuivasa-Sheck, who might be available to play for Auckland in this year's NPC, could played in all three positions.

That doesn't mean MacDonald has set in stone where the 28-year-old will play for the Blues, though.

"Roger played midfield at school and he obviously plays in the outside backs in league and I think we'd be foolish to make a call on that right now," MacDonald said after his side's Super Rugby Trans-Tasman final victory over the Highlanders on Saturday.

"He hasn't even donned a rugby jersey yet. We've got to get him out of the Warriors jersey first. We're hoping to see him in the NPC, potentially, later on in the year. They'll ease him back in.

"We share a building with Auckland so we'll be around to help navigate his way through the learning of the game."

Tuivasa-Sheck's arrival at the Blues will only bolster the Super Rugby Trans-Tasman champions' depth chart, particularly in the backline where there is no shortage of talent.

Despite the imminent departures of first-five Otere Black and midfielder TJ Faiane, the Blues will still have All Blacks stars Beauden Barrett, Rieko Ioane and Caleb Clarke to accompany Tuivasa-Sheck out wide.

MacDonald said having such breadth of quality will only serve the Blues well when it comes to finding a positional home for Tuivasa-Sheck.

"We've got the ability to change positions. Rieko can play midfield and wing, Roger could play on the wing early on or at fullback or in the midfield, so it's really what works out in the end and how it all folds together."

Working out just how Tuivasa-Sheck fits into the Blues' backline is even more intriguing when taking into consideration the rise of young fullback Zarn Sullivan.

The 20-year-old rookie had a memorable debut Super Rugby campaign as he started in the franchise's last seven matches of the season, including all six Trans-Tasman games, to play a crucial role in his side's title-winning success.

An intelligent player, Sullivan pulled the strings from the backfield as he proved his worth as a sublime kicker out of hand who constantly put opposing sides on the back foot with some sterling touch-finders that kept teams trapped inside their halves.

He also showed glimpses of his running ability and distribution skills, and he also looms as a quality long-range goal-kicking option.

That broad skill base has previously led MacDonald to express how he sees Sullivan's future in the No 10 jersey, despite the youngster having plied his trade exclusively at fullback this season.

However, with Barrett, Stephen Perofeta and Saturday's match-winning goal-kicker Harry Plummer all returning to Eden Park next year, opportunities to play at first-five might be hard to come by for Sullivan.

That could force the former King's College standout to stay in the No 15 jersey, which, in turn, may have implications on where Tuivasa-Sheck will play or how much game time he will receive.

Given MacDonald described Sullivan's skill set as "perfect" for a No 15, it seems Tuivasa-Sheck will have a battle on his hands if he wants to establish himself as a fullback in union, as he has done in league.

"We're keeping him [Sullivan] at the back at the moment," MacDonald said.

"We've obviously got Beaudy there and Oats [Black] is going, but Stephen Perofeta's playing good rugby and you saw Harry step up to the mark, so we're pretty blessed with some good depth at 10.

"I think he's [Sullivan] got the attributes to become a very good 15. The skill set is perfect as he just keeps growing in confidence and understanding. There's no reason he couldn't become a 15 full-time."