Fernando Alonso has revealed changes to the front end of F1 cars made for the "biggest challenge" on his return to the sport.
Alonso enjoyed a successful return debut season with Alpine after spending two years away from the F1 paddock.
Although the 2021 cars did not undergo wholesale changes from the year before, Alonso conceded modifications at the front of the cars had taken the most time to adapt to.
"The biggest challenge was probably the front tyres and the philosophy that every team has in terms of front suspension, front power steering, the feedback you get on the steering wheel," Alonso explained in a post-season media briefing, including GPFans.
"That's obviously very unique for each of the teams and the front tyre construction.
"They changed from 2020 to 2021 and that was a challenge, I think, for everybody.
"But it was more a challenge apparently for the people that changed teams at the beginning of the year and for me as well because I was two years out of the sport."
In 2020, as Renault, the Enstone-based team spent the year locked in a tense fight for third with McLaren and Racing Point.
Although the team failed to feature so prominently last year, the season was marked by a maiden victory for Esteban Ocon in Hungary and Alonso's podium return in Qatar.
"The most rewarding moments for sure were the highs and the moments that we performed a little bit better," added Alonso.
"Obviously, the victory from Esteban in Hungary, that was the best moment for us as a team.
"My podium in Qatar was obviously a very nice feeling but generally, it has been a good year for me."