The Lions opted not to call up a replacement for Scotland full-back Stuart Hogg, who suffered a cheek fracture in Saturday's 12-3 Crusaders win.
New Zealand see the Pacific islanders as a chance to flawless what they learned from watching the Lions in their tour matches, which include a victory against Super Rugby's unbeaten Canterbury Crusaders and defeats to the Auckland Blues and Otago Highlanders.
"We need to play like we did last Saturday against the Crusaders", assistant coach Neil Jenkins said.
"He's at the stage where he wants to do that".
"He never takes a backward step and we believe that those leadership qualities will serve us well on Saturday against a quality and determined Maori All Blacks team". "I guess he will bring them out from the United Kingdom".
It would be a monumental blow to the Lions squad if Farrell was sidelined for any longer than expected with the 25-year-old an integral part of Warren Gatland's first Lions side, forming a key partnership with blockbusting England cross-coder Ben Te'o.
The tourists have made no suggestions whatsoever about bolstering the ranks in their squad, though Wales are now in New Zealand ahead of facing Tonga in Auckland on Saturday.
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The Lions are already sweating on the full match readiness of tour captain Sam Warburton, who may yet not be in a position to start the first Test.
Warburton has been struggling with an ankle injury on tour and played 68 minutes, scoring a try in the Lions' 23-22 loss to the Dunedin-based Highlanders on Tuesday.
"I didn't think I was going to get picked for the Lions, I didn't think I had played enough rugby before then", O'Mahony said on Thursday.
It starts with the 1888 Native team that won 80 percent of the 107 games it played on a 14 month tour of the British Isles. "They push each other so hard, yet whoever gets the jersey knows he's got two guys behind him helping out as much as they can".
"I was only just told about being captain on Saturday, so I need to get that sunk in first", said O'Mahony, when asked if he could lead the Lions' Test side.
"Ryan Crotty will be right for next week", said Hansen.
The All Blacks, who have often appeared rusty in the first test of their global seasons, organised the game against Samoa to help with their preparations for the Lions.