Cagey Verstappen calls out Ferrari for US GP struggles

Max Verstappen says Ferrari's underperformance in Sunday's US Grand Prix was unsurprising, hinting that changes made by the Italian outfit in the wake of a technical directive published by the FIA on Saturday had impacted its performance.

Ferrari has been under the scrutiny of its rivals since the end of F1's summer break, with suspicions that the Scuderia's engine and performance gains were perhaps rooted in something illicit, compelling Red Bull Racing to solicit the FIA's opinion on a possible loophole involving engine fuel flow measurements.

F1's governing body published a technical directive in Austin on Saturday morning clarifying its stance on the matter and explaining why Red Bull's hypothetical fuel flow scheme -perhaps exploited by Ferrari - was illegal.

• Hamilton claims Ferrari has lost 'a bit of power' in Austin

Oddly, Ferrari's pace in qualifying wasn't at the level many expected, prompting comments from Lewis Hamilton who believed the red cars had "lost a bit of power" on Saturday afternoon.

But the SF90's speed in Sunday's race was also relatively depressed, with Charles Leclerc finishing a distant fourth while Sebastian Vettel was sidelined by a suspension failure after eight laps.

Asked if he was surprised by Ferrari's strange inability to remain in contact with the frontrunners in Austin, Verstappen said he was not.

"Oh, that’s not strange," he said, mischievously adding, "Why do you think? You can fill it in yourself" when asked to elaborate on his reply.

Speaking to Dutch TV Ziggo Sport, Verstappen was a lot more explicit.

"That's what you get when you have to stop cheating," he said. "This has been looked at very carefully, so of course we have to keep an eye on that."

Ferrari boss Mattia Binotto has forcefully denied that the Scuderia's power unit was violating the technical regulations in any way, even urging the FIA to investigate the SF90's engine.

Leclerc was made aware of Verstappen's accusatory comments after Sunday's race and shot back at his Red Bull rival.

"I think it’s a joke to be completely honest," said the Monegasque.

"He has no clue, he’s not in the team. So, we know exactly what we are doing and I don’t know why he’s speaking, he doesn’t know anything about us."

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