Lando Norris has warned Alex Palou that his Formula 1 debut in United States Grand Prix first practice will be "quite different" to what the IndyCar star is used to.
Palou - the 2021 IndyCar champion is replacing Daniel Ricciardo in FP1 at Austin as McLaren fulfils half of its requirement to run young drivers in practice sessions - Norris will be replaced by Pato O'Ward in Mexico.
Chip Ganassi driver Palou has undertaken extensive testing in the 2021 McLaren in the TPC scheme but has not yet driven the '22 breed of car on-track.
Regular race driver Norris says that while Palou "will do a good job" the lack of time available - just 60 minutes - will be a tough hurdle.
Norris warns Palou
"It's always tough coming into an FP1, especially in a car he's never driven before," Norris told media including RacingNews365.com.
"He's done some of the test days in the previous car, but this one is quite different, and on such a cool track as well. It's not going to be easy.
"It's not like you have a lot of time, especially with the tyres and things, like you don't get that many laps of feeling good grip and things.
"But he's an extremely good driver.
"I've known Alex, I guess almost since karting, and more personally probably in the last few years.
"But he's an incredibly good driver, very talented and he's in the car for a reason.
"He can give good insight, add some valuable details for us, help us out as much as possible.
"He'll do a good job."
Palou was the centre of a contract saga in the summer when he publicly refused the chance to stay in the #10 Ganassi entry in IndyCar - having committed to McLaren.
However, the expected vacant seat alongside Norris for 2023 went to Oscar Piastri, with Palou eventually agreeing to stay with Ganassi - but allowed to do F1 testing and FP1 sessions with McLaren when schedules allow.
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