F1 star Carlos Sainz dropped a two-word reaction under Marc Marquez's brother Alex Marquez's Instagram post, congratulating the fellow Spaniard on finishing as runner-up in the 2025 MotoGP season. The Marquez brothers have created history by becoming the first sibling pairing ever to finish first and second in a MotoGP season.Earlier this season, Marc and Alex Marquez made history when the latter claimed his first MotoGP win at the Grand Prix of Spain. This result meant that the two became the first-ever siblings to win MotoGP races.Now, more history has been created by the Marquez family, with Alex securing the runner-up spot for the 2025 MotoGP season with a second-place finish during the Malaysian GP Sprint in Sepang on Saturday. With Marc Marquez having secured his seventh MotoGP title at the Japanese GP, this means the brothers have finished the season as first and second in 2025.After securing P2 in Malaysia, Marc Marquez shared an Instagram post sharing his delight about the achievement."Mission accomplished! 💙 So happy to close out the season as runner-up and proud of the incredible team behind it all. Thank you for all the love and support! Now it’s time to enjoy it ✊🏼" View this post on Instagram Instagram PostWilliams F1 driver Carlos Sainz shared his reaction to this feat by Marquez and left a congratulatory message under the 29-year-old's post."Congratulations Alex!! 💪," he wrote (translated from Spanish). Carlos Sainz's comment on Alex Marquez's post - via @alexmarquez73 on InstagramAs he keeps tabs on his fellow countryman, Carlos Sainz is currently competing in the Mexico City GP. The 31-year-old has looked strong in the initial stages of the weekend as he hopes to put in a strong performance during qualifying at the Autodromo Hermanos Rodriguez.Carlos Sainz to face five-place grid penalty at the Mexican GPCarlos Sainz during FP3 - Mexico City Grand Prix - Source: GettyNo matter the result in qualifying for the Mexican GP, Carlos Sainz will have to serve a five-place grid penalty during the race on Sunday. This is because the Williams man has carried the penalty over from the US GP last week.Sainz's crash with Mercedes' Kimi Antonelli in the initial stages of the US GP forced him to retire from the race due to the damage he suffered. With the stewards having judged Sainz guilty for causing the collision, he was given a five-place penalty, which had to be carried over to the Mexican GP.Sainz has explained that he is disappointed to be getting the penalty, as he claimed that the crash "looked worse from the outside," and that he had previously made similar moves without getting penalized.But no matter his qualifying position on Saturday, he will have to drop down five places thanks to this. This means Sainz will be even more motivated to finish as high as possible during the session, on a track which should suit the Williams car.