Martin Brundle says it is "difficult to believe" Racing Point managed to copy last year's Formula 1 title-winning Mercedes car so well, praising the team for doing "an extraordinary job".
Racing Point opted to base the design of its RP20 car on the 2019-spec Mercedes W10, stressing it has done so legally despite an ongoing protest from Renault.
The team has enjoyed a huge upswing in form this season, locking out the second row of the grid in Hungary two weeks ago before Lance Stroll finished the race in fourth place.
Racing Point sits fourth in the constructors' championship, one point behind McLaren and 13 clear of Ferrari after three races.
Ex-F1 driver and current Sky Sports F1 pundit Brundle said it was "difficult to believe" Racing Point had managed to copy the 2019 Mercedes so well and understand it enough to make it work.
"To replicate a car that works, it is stretching my imagination on that," Brundle said in an interview with Autosport.
"Having said that, they do buy - in a legitimate way - the engine and gearbox, which fixes your rear suspension, pick-up points, and suspension elements.
"They buy everything they can.
"There's an awful lot of reference points on the car that they legitimately buy.
"And it's just there are bits underneath aero parts and all that. When they created this, they had to finesse it.
"So they've done an extraordinary job."
The FIA is currently reviewing a protest lodged by Renault against Racing Point following the last two races in Austria and Hungary, centring on the legality of the brake ducts on the RP20 car.
Renault has stressed that its protest also acts as a push for clarification from the FIA over the degree of collaboration allowed in F1, believing it may have a knock-on effect for future teams' models.
Brundle said it was only right for the practices to be questioned after such an improvement in form, but was confident any legality concerns would be allayed by the FIA.
"We're right to question it, as journalists," Brundle said.
"The FIA have been to see it. I'd imagine if you do a scan of last year's Mercedes and this year's Racing Point, that would verify that, but then I'm told the FIA have looked at all of that. And they're satisfied.
"I don't think it's for me to say. I absolutely will not use emotive words like cheating, or whether information has been passed.
"That would be illegal under the regulations. I don't think they want to or dare do that.
"It's incredulous that the car works so well, but then it's a good little team.
"The bottom line is if the FIA say they've checked out completely, and Mercedes and Racing Point say 'we worked under particularly the 2019 regulations, when this car was conceived,' what can we do?
"Apart from keep asking the questions like you've asked me. If they're trying to pull the wool over our eyes, we'll find out eventually, as has happened with Ferrari last year."
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