Gatland led the Lions to a series victory in Australia in 2013 using a tactic, dubbed "Warrenball", which involves sending big ball carriers crashing across the gainline to draw in defenders and then looking to exploit gaps out wide.
In a wide-ranging interview with Britain's Times newspaper on Tuesday, Hansen said he was working on the assumption that the 2017 Lions would be using the same tactics.
"We assume Warren’s not going to have an epiphany and change the way he plays," he said.
"But we’re only assuming that, we’re not believing it until we see them play and, with a tour, you do get to see the opposition play a bit, so we’ll be able to confirm one or two things prior to that first test."
Hansen used the interview to lob a few grenades, including a defence of All Blacks flyhalf Beauden Barrett after Gatland had suggested place-kicking could be an area of the game that gave an edge to the tourists.
"I don’t think we’ve lost a test match through his goalkicking,” Hansen said of the World Player of the Year.
"People are panicking because he’s not goalkicking for the Hurricanes. That was initially because he had a side strain and it was hurting when he was goalkicking.
"I know he can mentally cope with the task of goalkicking in the arena. As long as he is doing his training and going through his skill acquisition of goalkicking through the week, then it doesn't worry me if he is goalkicking on Saturday or not.
"There’s no doubt the Lions have got great goalkickers. Now, pressure is a funny thing and I know our guys have lived under that pressure for a long time.
"And while they might not have the stats to match, I believe and have faith they’ll kick the ones that matter."
Hansen also took aim at Gatland's comments that he was embarrassed to be a New Zealander when he witnessed the "arrogance" of the fans and country's media when the All Blacks beat Australia last year to win a record 18th straight test.
"Our fans are pretty well educated and even though Gats has called them arrogant, I don’t think they are arrogant, I think they are well informed and have high expectations of us," he said.
"And they know that this Lions squad is one of the best to have been picked for a long, long time."
"The Lions have got a lot of expectation of their own — 30,000 people are coming out to support them and they are coming out in expectation of their team playing really well and winning the series."
The Lions arrive in New Zealand on Wednesday with the first of three tests taking place in Auckland on June 24.
(Reporting by Nick Mulvenney; Editing by Peter Rutherford)
