Daniel Bryan to officially announce his retirement on WWE Raw

ABERDEEN, Wash., Feb. 8 (UPI) -- Former WWE World Heavyweight Champion Daniel Bryan is set to announce his retirement Monday on Raw.

The fan-favorite superstar and Yes movement leader shared the sad news on Twitter Monday, mentioning that he would elaborate more on the circumstances surrounding his retirement on WWE's weekly flagship program.

"Due to medical reasons, effective immediately, I am announcing my retirement," Bryan wrote.

"Tonight on Raw, I'll have a chance to elaborate. #gratitude."

Bryan's last major match took place at WrestleMania 31 back in March of 2015 after he won the WWE Intercontinental Championship. Shortly after, Bryan abstained from in-ring action and relinquished his title after suffering from a concussion-related injury.

Bryan, who signed with the WWE in 2009, has held every major title within the company and is a four-time World Heavyweight Champion.