Blues interchange forward Josh Jackson has been receiving advice from former St George Illawarra hooker Nathan Brown about playing dummy-half if he is needed to step into the role during Wednesday night's Origin decider at Suncorp Stadium.

With doubts about Robbie Farah increasing after his involvement at training on Sunday was restricted and he was unable do a push-up before the opposed session, NSW coach Laurie Daley is expected to officially call in Michael Ennis once his one-match suspension expires on Monday night. But Jackson will be the back-up to whichever hooker starts.

Jackson has not had to perform the dummy-half duties so far in the series but he was told to get ready to do so after Farah suffered a shoulder injury just before half-time in Origin I and the Canterbury backrower said Brown had been helping him prepare for the role if needed.

"We've got Nathan Brown on the coaching staff and he obviously used to be a hooker so he has been in my ear a bit about what to do and how to play the position," Jackson said of the ex-Dragons, Huddersfield and St Helens mentor.

"I haven't played too much at hooker but if I get called in there, I will be ready and in game one I was prepared to come out in the second half and play well. I obviously won't have the same impact as Robbie but if I get called in there, I will just do my best."

Farah's recovery from hand surgery last Tuesday remains ahead of schedule but three days out from Origin III, it appears that time will beat him after Ennis again filled in at dummy half on Sunday in the Blues' final training session before moving from Coffs Harbour to Brisbane to finalise preparations for the match.

With NSW players having a day off on Monday, the Blues will have just one training session in Brisbane and Daley wants to have his side finalised by then.

In a sign that Daley is genuine about giving Farah every chance to play, Fairfax Media was told that Ennis will wear the No.18 jersey if he is called into the Blues team. Daley and Farah did a number of passing drills at the beginning of the session but when the Wests Tigers captain was required to do a push-up as part of a team bonding session, he declined.

However, no-one in the NSW camp was prepared to rule him out of the match until an official decision is made.

"Hopefully he will come through well and play," Jackson said. "He is a tough bloke, he has shown that with his shoulder injury and in Origins in the past."

Fellow forward Trent Merrin said: "It's incredible the way that Faz is going about the job. You couldn't even tell that he had an operation a few days ago. He's continued to improve with his hand so he's giving himself every chance possible."

Before catching a charter flight to Brisbane on Sunday, the Blues went through their second contact session of the camp, which including an opposed session against players from local team Coffs Harbour Comets and NRL stars Tariq Sims, Alex Johnson, James Roberts, Joey Lussick, Will Smith and Sione Mata'utia.