Lawson will replace Daniel Ricciardo at RB for the balance of 2024 and is in the frame for a potential drive with Red Bull Racing in 2025.
The New Zealander’s place on the grid comes after having worked as reserve driver for both of Red Bull’s F1 operations since 2022.
He had a five-event cameo in place of Ricciardo last season after the Australian broke his hand during practice for the Dutch Grand Prix.
That catapulted him into contention for a race drive, though he was initially overlooked for 2024.
Without a racing program, he has instead spent time completing a number of test days aboard older spec machinery.
He was scheduled to drive the current-spec RB at Imola following the Belgian Grand Prix, though plans changed and he instead piloted an AlphaTauri from 2022 while Ricciardo and Yuki Tsunoda shared the current car.
That outing had been billed as a head-to-head evaluation between Lawson and Ricciardo, though that was walked back as a decision was made to retain the latter in the short term.
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“No, it was,” Lawson insisted when asked by Newstalk ZB whether it was indeed part of an evaluation.
“They were all evaluation days and they were designed to put lots of pressure on me.
“Basically, it was for an event like this where, to throw me in, a bit like last year, throw me in mid-season, they needed to know that obviously, I’d somewhat performed.
“They were definitely evaluation days.”
While those outings were a way for team bosses to assess his progress, they were also a useful means of staying up to speed given his lack of race program this year.
As reserve driver, Lawson has been present at the track on race weekends and completed simulator duties alongside Sebastien Buemi.
He’s also recently had time at the wheel of this year’s Red Bull Racing machine at Mugello in a Pirelli tyre test, banking more than 100 laps.
Those experiences combine to lower the hurdle the Kiwi will need to clear upon his F1 race return.
“It’s always a big jump,” he confessed.
“It’s going to be tough to jump in Austin, I haven’t done [Circuit of The Americas] before either, so even I’ve done plenty of some work, it’s going to be a big challenge.
“But I would say I’m better prepared, definitely more prepared this year than I was last year.
“At the same time, it’s slightly later in the season this year, so these guys have done three quarters of a season, and there’s nothing like… obviously, I’ve been training like crazy all year to try and be ready for something like this, but even the few tests that I’ve done this year, it’s, there’s nothing like being race fit.
“It’s going to be challenging in Austin.”
The United States Grand Prix begins on Friday with opening practice from 12:30 local time (04:30 AEDT Saturday).