Sebastian Vettel admits he is not expecting to still be in F1 when he turns 40, unlike Fernando Alonso.
Alonso - who returned to Formula 1 with Alpine this season following two years away from the sport - recently celebrated the milestone birthday. Vettel, 34, wouldn't rule out still being in F1 when he reaches that age himself but believes it is not likely to be the case.
"No, I don't think so," Vettel told media including RacingNews365.com when asked if he would still be racing in Formula 1 at 40.
"But, as you asked Fernando [who said he hadn't expected being in F1 at 40], you never know, but right now I would say no."
Vettel made his debut in Formula 1 in 2007 at the age of 20. The German went on to win four world titles with Red Bull between 2009 and 2013, so had already achieved a great deal before even turning 26.
Meanwhile Alonso first raced in F1 back in 2001 with the Minardi team. The Spaniard - who claimed his two world championships in 2005 and 2006 - is now competing in his 18th season in Formula 1.
Throughout their careers, Vettel and Alonso have been involved in many on-track battles and Vettel says he has enjoyed being able to compete against the Alpine driver again since his return to the sport.
"The first race that Fernando was back this year, we had some wheel to wheel, and I was actually smiling in the cockpit because I'd been looking forward to more of it this year, and I think we had a little," the four-times World Champion explained. "I always enjoy [racing] Fernando."
They might be two of the older drivers on the grid but Vettel and Alonso both showed their mettle in the recent Hungarian Grand Prix. Alonso battled with Lewis Hamilton in the latter stages of the race and impressively kept the Mercedes behind for as long as possible, meaning that Hamilton was unable to catch Alonso's teammate Esteban Ocon in the lead.
Meanwhile Vettel finished the chaotic Grand Prix in second, but was later disqualified due to the FIA being unable to take enough of a fuel sample from his car at the end of the race. Aston Martin have confirmed that they will formally appeal against the penalty.
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