Both coaches sprung surprises in naming their starting XVs for the eagerly anticipated clash at Auckland's Eden Park on Saturday.
The inclusion of fit-again Kieran Read ahead of Ardie Savea was to be expected, but Steve Hansen has also opted for Ryan Crotty and Rieko Ioane at outside centre and left wing respectively, taking the places of Anton Lienert-Brown and try-machine Julian Savea.
"I'm not sure, looking at their bench, that it is as strong as it has been in the past," Gatland said of the 2011 and 2015 Rugby World Cup winners.
"We were surprised by Crotty being selected at 13 and Savea, who has been a constant for them, being replaced. I know how good Ioane is, but this is a big game for everyone."
— All Blacks (@AllBlacks) June 22, 2017
New Zealand thrashed Samoa 78-0 last weekend in what was their first match since beating France in Paris in November.
And the tourists' coach claimed his countrymen may be feeling rusty when they go up against a visiting side hardened by six tough tour fixtures.
"They went and arranged the Samoa game because they feel potentially they're going to be a little bit undone," Gatland said.
"How that helps their preparation I'm not too sure as they've been together for the last couple of weeks.
"We've taken on an incredibly tough schedule, like nothing the Lions have ever faced.
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— British&Irish Lions (@lionsofficial) 23 June 2017
"Sometimes in the past, midweek teams have been a bit of a frolic but we've been tested all the way. In terms of the opposition, the preparation and the intensity of matches, it has been really beneficial.
"We think we are in a good place at the moment. We really think we have been improving week to week, we have stayed tight as a group and we haven't let anything externally have an impact on us. We haven't had any players moaning about anything – they've just got on with their jobs."
The Lions will be aiming to become the first team to beat the All Blacks at Eden Park since 1994.
Photo by Getty Images: British and Irish Lions coach Warren Gatland