WWE Superstar Daniel Bryan gave an emotional goodbye to fans on 'Raw', Monday night, after announcing his retirement from the ring due to medical reasons. Bryan, 34, made the difficult decision to hang up his boots after suffering multiple concussions throughout his wrestling career.

Brie Bella and Daniel BryanDaniel Bryan (pictured with wife Brie Bella) has announced his retirement from wrestling.

Bryan announced his retirement on twitter Monday afternoon telling fans: ‘Due to medical reasons, effective immediately, I am announcing my retirement. Tonight on Raw, I'll have a chance to elaborate. #gratitude.’

After being forced to take time out due to injuries in April of last year, Bryan had been awaiting clearance to wrestle by WWE doctors and undergone multiple medical tests. However he recently learnt that he would not be given clearance due to his history of concussions.

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In an emotional speech on Raw, from his home state of Washington, Bryan (real name Bryan Danielson), told fans: “Within the first five months of my wrestling career, I’d already had three concussions.”

“For years after that, I would get a concussion here and there, or here, or there, and it gets to the point when you’ve been wrestling for 16 years that it adds up to a lot of concussions. It gets to a point where they tell you that you can’t wrestle anymore.”

“I have loved this in a way that I have never loved anything else. But a week and a half ago I took a test that said maybe my brain wasn’t as OK as I thought it was. And I have a family to think about, and my wife and I want to start having kids soon.”

In 2014 Bryan became the focal point of the WWE’s build to Wrestlemania 30, after overwhelming fan support eventually led to him being added to the main event title match. Bryan would go on to win the WWE World Heavyweight Championship on April 6th in New Orleans, beating Randy Orton and Batista in a triple threat match.

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While Bryan didn’t have the traditional build of a WWE Superstar, his wrestling skills, which were honed during his time on the independent circuit and at Ring of Honour, made him one of the promotion's most valuable and loved stars.

He became well known for his trademark long beard and ‘Yes! Yes! Yes!’ chant, as well as his easy-going yet charismatic promo-style. Since he announced his retirement thousands of fans have been expressing their gratitude to Bryan and remembering some of his most famous matches, as #ThankYouDanielBryan trended worldwide on social media.