Last season Triantis captained Sydney FC's youngsters to glory in the inaugural National Youth League competition, and will provide some much needed cover for the Jets in the centre of midfield.

The hard-working 21-year-old was not retained by the Sky Blues for thisseason, but Jets' boss Branko Culina has brought the youngster up to the Hunter from Sydney Olympic, where he was playing in the NSW Premier League.

Wheelhouse, meanwhile, faces at least six weeks on the sidelines as he recovers from a torn lateral ligament in his right ankle which he injured during the Jets' final pre-season trial match last Wednesday night.

Triantis has been training in Newcastle since the beginning of this week and is likely to be rushed into the squad for the Jets' home clash against Wellington Phoenix this Sunday, August 9.

Club CEO John Tsatsimas was delighted to welcome Triantis to Newcastle today.

"Chris is talented player and we all watched with interest the progress that he made last season," he said. "Obviously, since then, we've brought in Sean Rooney from that same youth team, and we see Chris in a very similar manner.

"He is a good young player who can fulfil a role for us in the middle of the park, which is something that we need at this point in time given our injury toll."

Wheelhouse joins a current Jets injury list which includes Ben Kantarovski, Donny de Groot, Marko Jesic and Shaun Ontong.

Tsatsimas added: "Needless to say that we wish Jobe a very speedy recovery and we very much look forward to him being back on the pitch.

"Unfortunately he has not had much luck with injuries throughout his career but we certainly hope that his rehabilitation goes as smoothly as possible."