Robert Downey Jr stuns fans with blue hair transformation

Robert Downey Jr. during the filming for the Graham Norton Show at BBC Studioworks 6 Television Centre, Wood Lane, London, to be aired on BBC One on Friday evening.
Robert Downey Jr usually has dark hair. (PA)

Robert Downey Jr has stunned his fans by unveiling a dramatic hair makeover.

The Iron Man star, 57, usually sports a head of dark brown hair, but has dyed it blue.

He unveiled his bold new look in a snap on Twitter that showed him and his wife cheering on their son's baseball team.

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The picture showed Downey Jr clean shaven and with close cropped hair dyed a striking shade of blue, which matched his sunglasses.

The actor appeared to have dyed it to support a local baseball team, sharing in a separate post: "Congrats are in order for the Malibu Little League 2022 AAA champs! Big thanks to Coach Alfano, Coach Sullivan and Coach Mark. Dodgers brought the heat!!!"

His fans were blown away by his transformation.

"What happened Mr Stark?" asked one fan on Twitter, referring to the actor's Iron Man role.

"BLUE HAIR KING," said another.

One person posted: "I love the colour! It’s fantastic!"

Robert Downey Jr attending the Captain America: Civil War European Premiere held at Vue Westfield in Shepherd's Bush, London.
The actor has a new look. (PA)

Someone else said: "You wear it well sir! That's such a gorgeous shade of blue!"

"Diggin the colour!" one admirer tweeted, while another commented: "Love it."

"I'm assuming the blue hair is to show support for the little league team which is blue and white colours," they explained.

Robert Downey Jr. and his wife, Susan Levin, arrive for the
Robert Downey Jr married wife Susan in 2005. (PA)

Downey Jr tied the knot with his wife Susan in 2005.

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They welcomed their son Exton in 2012 and two years later they had a daughter, Avri.

The actor also has a son from his former relationship with actress and singer Deborah Falconer.

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