As the release of Spider-Man: Homecoming nears, Marvel Studios finds itself at a crossroad. With the first phase of the MCU set to wrap after the dual Infinity Wars movies, the studio must decide what to do with its aging roster of superheroes.

Does it let the likes of Iron Man, Captain America and Thor ride off into the sunset while embracing the new guard? Or does it recast its veterans and find a way to integrate them into their new superhero landscape?

Well, it looks like Robert Downey Jr. is going to make at least part of that decision somewhat easier. According to the actor, who’s played Tony Stark since 2008, his days of busting skulls and cracking wise as the de facto leader of the Avengers may soon be behind him.

“It’s this cyclical thing. I could have said when the first Avengers came out: ‘It’s never going to get any better than that. Everybody stop.’ But to me, it’s always about people and opportunities, like the (‘Avengers’ directors Anthony and Joe) Russo, who I adore,” he told News Corp Australia Network.

“Everyone says to me it’s like a glove that fits so well. I have to start over every time but I am starting over with a pretty solid base. I just never want to blow it for the last six or seven (Marvel Cinematic Universe movies) I have done by dropping the ball because I decided to go do it one more time. I just want to hang up my jersey before it’s embarrassing.”

Now that Downey Jr. has come to terms with the fact that the one rival he can’t defeat is Father Time, it’s time to look forward. Theoretically, Downey Jr. could play Tony Stark well into the next decade. Harrison Ford was a septuagenarian when he last played Han Solo and Tom Cruise will be nearly 60 the next time he plays Ethan Hunt in the upcoming Mission: Impossible movie. Downey Jr. is just 52, which puts him on the lower end of the aging hero spectrum, but well ahead of the curb when compared to his counterparts (Spider-Man’s Tom Holland is just 21).

That age gap between Downey Jr. and his counterparts works because in many ways, Stark is the patriarch of the MCU, a fact never more apparent than in Homecoming.

But if and when Downey Jr. does decide to leave, and Marvel wants to keep Iron Man around, it will have to cast someone with the same gravitas as Downey Jr. One of the most impressive aspects of the MCU is the way in which it moves in real time. We age as the characters age, which means a younger Iron Man would ring false. Unless of course, Marvel decides to reboot the character altogether by giving us another Iron Man origin story.

Judging how savvy the studio has been in unfurling its various tentpoles, it’s unlikely it goes that route. That means one thing: Let the Colin Farrell as Iron Man movement begin!