Alfa Romeo team boss Frederic Vasseur says Guanyou Zhou's full release from Alpine's management was a prerequisite for his hiring by the Swiss outfit.
Zhou will join Valtteri Bottas at Alfa Romeo next season, having spent the last three seasons in the FIA Formula 2 Championship with the UNI-Virtuosi Racing outfit and as a member of the Renault Sport Academy.
Alfa's short list for its second seat in 2022 reportedly included both Zhou and fellow Alpine junior Oscar Piastri.
While the French manufacturer appeared interested in only loaning the 20-year-old Aussie to Alfa, it was willing to release Zhou entirely from his Alpine commitments, and that decision was crucial for Vasseur.
"He is no longer managed by Alpine and is no longer under contract there," Vasseur told Germany's Auto Motor und Sport.
"That was important to me because I have to be free and be able to work towards the future. A one-year project, if I knew there was no chance for 2023, makes no sense.
"I have a good relationship with Alpine and it is also important to me to be very open and to discuss the situation with them.
"In the end, it is a good story for them too – they helped him get into Formula 1.
"With each driver, you also have to look at the circumstances. Piastri, for example, has a contract with Alpine.
"We probably could have had him for only one year. I wanted to have a free hand in my options for the future."
Alfa Romeo was the last team to announce its complete 2022 line-up, in part because Vasseur wanted to see how this season's F2 campaign - in which its candidates for its second seat were racing - would unfold.
"That would have made sense because in Formula 2 there is the problem that the champion cannot race there in the following year," he said. "But we can’t wait until December 10.
"In terms of recruiting drivers from Formula 2, it would certainly be better if the championship ended earlier.
"With Zhou, we know where we stand. He has performed well in Formula 3 and Formula 2, drove a fantastic pole position this year at Silverstone and has always been there in the races.
"I have great confidence in him."
Gallery: The beautiful wives and girlfriends of F1 drivers
Keep up to date with all the F1 news via Facebook and Twitter
McLaren's successful 1-2 finish in the Brazilian Sprint race came with a dose of complexity,…
Max Verstappen has been demoted from third to fourth in the final standings of Saturday’s…
Lando Norris secured victory in Saturday’s Sprint event in Sao Paulo thanks to a McLaren…
McLaren clinched a valuable 1-2 sweep of the São Paulo sprint race, with polesitter Oscar…
Full results from the Sprint race for the São Paulo Grand Prix at São Paulo,…
Fernando Alonso and Lance Stroll will start Saturday's sprint race at Interlagos from the pitlane…