Now, poised to become an NRL assistant to Steve Price next year, he has been endorsed as a future coach at St George Illawarra.

McGregor may be missing the blond locks like Cameron Diaz to complete the gag, but indeed, there truly is something about 'Mary'.

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After three premierships with Illawarra league club Wests, then a return to the NRL system with the NSW Cup feeder team the Cutters, McGregor is once again part of the Dragons' inner sanctum.

This week, Fairfax Media revealed McGregor is to replace Steve Folkes next year, which looms as a defining season in Price's career.

McGregor is also again playing a key role in the NSW State of Origin camp, part of Laurie Daley's team alongside the likes of Brad Fittler, Trent Barrett and Steve Roach.

Roach reckons McGregor is destined for the NRL.

"He's the ultimate professional, as he was when he was playing," Roach said.

"He's done his apprentice, done the strength and conditioning, the water running, the delivering of messages to the players, the GPS training, coached at a lower level, then into the Origin scene, and of course with the Cutters, so he's ticked every box of a coaching apprenticeship.

"He's a hard worker, so it doesn't surprise me he's being promoted at the Dragons. He deserves his go. His time is here and I wouldn't be surprised if he's even being groomed to take over from Price at some stage, possibly sooner rather than later even."

As part of the restructure, Dean Young would take over as Cutters coach, with 2010 premiership captain Ben Hornby taking charge of the National Youth Cup under-20 team.

Justin Holbrook will join McGregor as Price's assistant.

While the Cutters have had their struggles since entering the NSW Cup as the Dragons' reserve outfit, McGregor is credited with making the new venture a competitive force.

"Players want to play for Mary," Roach said. "The thing with coaches is you've got to be able to attract players to play for you and he's convincing. .

"I feel for Folkesy, given he's not long lost his wife and now he's lost his job but he'll bounce back. He's a tough human being and he'll understand the reasons behind all of this I'm sure."

Former Dragons halfback Mat Head credits McGregor for his emergence as an NRL player.

Head made his debut in 2003, when McGregor was the strength and conditioning coach, a position he remained in until coach Nathan Brown was replaced by Bennett.

McGregor then went on to complete a famous threepeat of premierships with Wests in the Illawarra league, breaking an 18-year drought when the club won in 2009.

"Mary and myself were both Dapto boys, so when I came into grade, Mary was always that guy I could speak to when I needed to," Head said.

"A couple of times, when there were players ahead of me at the club, I wondered where the chances would come for me and whether I should leave the club and Mary always got me back on track."

Wests coach Reece Simmonds, the former Dragons and Rabbitohs player who was captain during the recent premiership reign, said McGregor's dedication provided the Red Devils with a competitive edge.

"The club wasn't too far away from where it needed to be anyway," he said. "But when he took over at Wests, his dedication and work ethic was a big factor [in the club's success]."

However, Head warned against thoughts of McGregor being a short-term fix, if Price struggles again next year with new buys Gareth Widdop, Joel Thompson, Dylan Farrell and Englishman Mike Cooper, as well as mid-season recruit Josh Dugan.

"The good thing about Mary's career is he hasn't rushed anything," Head, who coached Balmain to the SG Ball premiership this year, said.

"He has been in the system before, went back to coaching in the Illawarra league and is now back in the NRL, Origin and Country.

"I've no doubt he's got everything he needs to be an assistant next year and then, well, you would think his time would come at some stage."