#1 - Daniel Bryan compresses a nerve in his neck, returns, then gets his tenth diagnosed concussion (2014-2015)

One could feasibly argue that Daniel Bryan is the greatest babyface in WWE history. A naturally-likeable plucky underdog, Bryan was easily the most technically gifted wrestler on the WWE roster in the early 2010's. When he finally won the WWE World Heavyweight Championship at WrestleMania XXX, the crowd reaction was deafening. It was such a remarkably cathartic moment in wrestling history that it gave birth to the now-banal "you deserve it" chants. Long story short, it was awesome.
And then he got two bits of bad news.
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Shortly after WrestleMania, Bryan's father passed away. Then, he started losing feeling in his right arm, to a point where he couldn't even unlock his car door. He discovered that he had a compressed nerve root in his neck, which would require a minimally-invasive surgical procedure to correct. Because "minimally-invasive" implied "not too severe," Bryan held onto his Championship, as WWE assumed that he would be back soon.
Months later, he was still in pain. As a result, he was stripped of the Championship in time for that year's Money in the Bank PPV, and doctors could not provide a timetable for his return. There was even some buzz that the injury would force Bryan to retire altogether. Luckily, on December 29th, he revealed that he would be wrestling in the 2015 Royal Rumble and would not have to retire.
Yet.
Despite the fact that he was still the most over babyface in the company upon his return, WWE refused to give Daniel Bryan his contractually-obligated rematch for the title he never lost. Instead, the rub was given to Roman Reigns, much to the crowd's disdain. Still, Bryan would end up winning the Intercontinental Championship in a thrilling multi-man ladder match at WrestleMania 31.
Just weeks later, he was gone again.
His scheduled title defence against Bad News Barrett at 2015's Extreme Rules PPV was cancelled, as Bryan was deemed "medically unable to compete". A month later, Bryan announced that an MRI revealed that he would have to go on the Disabled List for an undetermined amount of time...again. So, he would have to relinquish his championship...again. Once more, fans waited with baited breath, wondering if Bryan would eventually return or whether he would be forced to retire.
Sadly, it was the latter.
In February of 2016, Daniel Bryan officially announced his retirement from professional wrestling. Though he felt like he could wrestle, a new test revealed that Bryan's reflexes had slowed down and that he had a small lesion on his brain, which explained his post-concussive seizures. He did not want to retire (and he still doesn't), but the revelation forced his hand. Absolutely heart-wrenching.
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