Andrea Kimi Antonelli has beaten Jack Doohan in taking race car number 12 next season, after both set their sights on it.
Under Formula 1's current sporting regulations, drivers have to choose a permanent number that they keep for their entire F1 career.
Numbers only become available if a driver's F1 career is deemed to have ended after two full seasons out of grand prix racing.
The number 12 has been available since the start of 2019, with Brazilian Felipe Nasr having used it during his two seasons in F1 in 2015 and 2016.
With several rookies stepping up to F1 for next year, an interesting situation had emerged with Alpine's Doohan and Mercedes' Antonelli both after the same #12.
Speaking recently in an Instagram reel in the wake of signing his 2025 Alpine contract, Doohan said that he planned to be racing with #12 next year.
"I'm pretty sure it's quite known now but I will choose #12," he said. "I've been thinking about it over the summer break and then we locked it in, so 12 will be the number I start my Formula 1 season with."
However, unbeknown to Doohan and Alpine, it is understood that Mercedes had already kicked off the process of applying for Antonelli's race number for 2025 – which was also #12.
Motorsport.com understands that FIA protocol, in the event that two drivers request the same number, is for it to be given to the first one that has applied for it.
In this case, multiple sources have indicated that Mercedes got there first, which means that Doohan will need to pick a different number for 2025.
Speaking at the Italian Grand Prix about the significance of his race number choice, Antonelli explained that he liked it because of its link with Ayrton Senna, who raced with #12 from 1985 through to his title-winning 1988 campaign.
"Yeah, I will take 12," he said. "I have many numbers that I like. But 12 is a special one, also because of an idol. I've been using it since F4. It always went well with 12. So, no reason to change it for next year."
Antonelli ran with the #12 during his brief FP1 outing at the Italian Grand Prix.
Each team has its own nominated, consecutive numbers for FP1 rookie drivers to run with - Mercedes holding the numbers 42 or 43 for practice outings.
However, running #43 was not possible because Williams rookie Franco Colapinto has chosen that one as his permanent race number for the rest of the season.
With Mercedes not wanting to run #42, special permission was granted for Antonelli to run with #12 already.