'Avengers: Infinity War' Director Says Robert Downey Jr. Is Fantastic On Set

Robert Downey Jr. kicked the Marvel Cinematic Universe off in 2008 with his role as Tony Stark in Iron Man and now, fan-favorite director Joe Russo can't help but praise the superstar actor.

At a press junket in Singapore promoting Avengers: Infinity War, Russo was asked what it was like working with Downey on set. The director didn't have a bad word to say.

"Robert's fantastic. Robert is really focused and he works incredibly hard," said Russo. "There's a reason he's the biggest movie star in the world: he's put in the work. He's awesome to have on set."

When Infinity War debuts next week, it will mark Downey's ninth appearance in the Marvel Cinematic Universe. Outside of his trilogy of solo Iron Man movies, Downey has appeared in The Avengers, Avengers: Age of Ultron, and Captain America: Civil War while serving up cameo appearances in The Incredible Hulk and Spider-Man: Homecoming.

As of this writing, the only two movies Downey is slated to appear in are Infinity War and the still-nameless Avengers 4. The actor himself has even went the length to admit he's thought about his MCU exit, making sure he leaves the shared universe in the best possible shape.

Previously asked about the actor's exit from the MCU, Russo said Downey is simply irreplaceable.

"There is nobody who can take over Iron Man from Robert," Russo said. "I don't think the audience would accept that. He never mentioned to us about leaving Iron Man, but it will happen at some point of time.

He can't play the character forever," Russo continued. "I am sure there are lots other things he wants to do in his career. But he loves playing the character, I know that, and we love working together. We will see where it goes from here."

Infinity War and Avengers 4 mark Downey and Russo's second and third times working together after the two both played a part in Civil War.

In addition to the pair of upcoming Avengers movies, Russo co-directed both Civil War and Captain America: The Winter Soldier with his brother Anthony.

On a scale of 1 to 10, what's your hype level for Avengers: Infinity War? When do you plan on seeing it? Let us know in the comments!

Avengers: Infinity War releases on April 27th. Other upcoming Marvel Cinematic Universe movies include Ant-Man and the Wasp on July 6th, Captain Marvel on March 8, 2019, the fourth Avengers movie on May 3, 2019, the sequel to Spider-Man: Homecoming on July 5, 2019, and Guardians of the Galaxy Vol. 3 in 2020.