RaceFans has reported:

Mercedes was so struck by Andrea Kimi Antonelli’s pace in Formula 4 that it replaced his engine during the season to check whether his results reflected a car advantage. The Italian driver continued winning after the swap, according to James Vowles, who recalled that he, Mercedes team principal Toto Wolff and the team’s young driver programme head, Gwen Lagrue, discussed whether the team’s chassis and engine might be influencing their assessment.

Vowles described Antonelli’s first full year in single-seaters as a striking change from karting. “He was fantastic in karting, but you’re never quite sure how karting will translate into single-seater,” Vowles told the official Formula 1 channel. He said the gap to other drivers was unusual for the category.

“But it was the first year of single seater where he didn’t just win, there was a gap of two-and-a-half tenths between him and anyone else,” Vowles said. “That doesn’t happen in Formula 4. Everyone put it down to ‘he’s done lots of testing’ [but] he didn’t: he did six days of testing.”

Vowles said the three Mercedes figures wanted to establish whether Antonelli’s advantage came from his driving or the equipment. “What we also had a question - and this was between Toto, myself and Gwen, we were having this conversation - do we have just a bias [because] we’ve got a good chassis and good engine?”

The team changed the engine at one point in the season. “So at one point in the season, we took the engine out and put another engine in. We purposely swapped it around and still went on to win,” Vowles said. The results reinforced his view of Antonelli’s ability. “So at that point, if you’d asked me, I would have said that he’s very, very good. I’ve rarely seen that transition into it. And he continued that on through his junior career.”

Antonelli won 13 of the 22 races in that Formula 4 season. The following year, he won the Formula Regional European Championship, after which Mercedes chose to accelerate his path towards Formula 1 by moving him directly into Formula 2 and preparing an aggressive programme in the background.

“Mercedes did a very brave call, and the right call, which was to move him up all the way into F2 straight away and then to a very aggressive [F1] programme in the background,” Vowles said. He added that the rapid promotion had a cost early on. “And I think without doubt, he probably suffered from the fact that it was a very fast acceleration into F1. So he had a year of playing catch-up.”

After a difficult first Formula 1 season, Antonelli has made substantial progress this year. He leads Mercedes team-mate George Russell by 84 points in the championship standings, with seven rounds remaining. Vowles said the improvement had surprised him, even as he praised Wolff and the team for backing the young driver.

“Well done to Toto and the team, [it was a] brave call. Absolutely came out trumps on top of it. Great belief,” Vowles said. “Because at times, if you read some of the headlines, everyone was questioning what they were doing. I knew underneath that he had a huge performance.”

Vowles said Antonelli’s gains extended beyond speed, pointing to his ability to avoid mistakes while managing races. “The step he’s made this year I think probably caught most people out. Maybe not the team, maybe they had more awareness of this, but for me I’m very impressed with the jump he’s made.”

“Because it’s not just the pace that comes with it, there’s no mistakes that go with it either. Particularly [because] he’s in control of the situation,” Vowles said. He cited Antonelli’s drive at Monza, where the driver moved from the back of the grid to the front. “He carved his way from the back of the grid to the front at Monza. That’s a mature drive. It’s a hard drive to do. I think I looked at it on that one. I thought, how the hell’s he made eight positions up? Anyway, good on him.”