Rocketman star Taron Egerton collapses on stage mid-performance

Actor Taron Egerton, best known for his lead role in Rocketman, was performing on stage in front of a packed crowd on opening night of his new theatre show, when he suddenly collapsed.

The 32-year-old actor is appearing alongside Bridgerton star Jonathan Bailey in London's Leicester Square, but he passed out on stage on Saturday evening (UK time) and wasn't able to finish the show.

Taron - who was replaced by his understudy Joel Harper-Jackson - subsequently wrote on Instagram: "As some of you may have heard, I passed out during the first performance of COCK last night.

Egerton was performing alongside Jonathan Bailey in opening night for the play Cock, when he passed out on stage and wasn't able to finish the show. Photo / Getty Images

"I am completely fine. Slightly sore neck and a bruised ego, but I'm fine.

"I've decided to put a positive spin on it and I would appreciate it if anyone who was in the theatre last night just said that I gave such a committed, electrifying performance that my body couldn't handle it and checked out. That being said, apparently you're meant to actually do the full show and not just three quarters of it."

Taron - who previously played alongside Colin Firth in Kingsman - also confirmed he's set to return to the stage on Monday.

His post continued: "I'll be back with a vengeance tomorrow night. Thank you to the amazing team at the theatre and my wonderful cast mates for being so lovely.

"But mainly I wanted to say thanks to Joel Harper Jackson who stepped in to do the last bit of the play.

"Joel is an amazing actor and a lovely person. Thank you, Joel. T x."

The production team also released a statement after Taron fainted on stage.

The statement read: "During this evening's first preview of Mike Bartlett's play Cock at the Ambassadors Theatre, Taron Egerton fainted towards the end of the performance.

"A doctor who was in the audience attended to Taron immediately after the incident, and whilst he felt fine, it was decided that Taron's understudy, Joel Harper-Jackson would continue in the role to complete the performance."