That's when his self-proclaimed old-school mentality took over.
Fletcher, who has the NFL's longest active consecutive games streak at 240, said his neck started bothering him, leading to balance issues. He didn't tell the team until midway through the season. Once he did, it led to the issue being resolved -- and a much better second half to his year.
But it also led to insight Thursday about Fletcher, his mentality and his thoughts on concussions.
"It's football. I play inside linebacker, and I like to play physical," Fletcher said. "It can happen a couple times a game, but I wouldn't classify them as concussions. They're just a little bell-ringing. You see stars for a second, and then you're back to normal in two to three seconds. It's just the way the game is."
Fletcher suffered a concussion in the first preseason game last summer after a first-quarter collision with safety Madieu Williams while breaking up a pass. Fletcher was given a veteran's day off the following week and then more time. He did not play in the following preseason game versus Chicago, nine days after the Bills game, which raised eyebrows given how little time he had sat out in previous camps.
He deflected questions about whether he had a concussion, as did coach Mike Shanahan, who addressed the issue Thursday.
"He hasn't had very many injuries that would set him back, and to have an injury like that where you're not really sure what it is, it was really tough on him," Shanahan said. "He did everything he could to get the proper attention, but I think it was tough on him for a while because he wasn't really sure what it was."
Fletcher's baseline numbers soon returned to normal, allowing him to return in the preseason.
Fletcher continued to play in the regular season, but his performance took a hit. He missed more tackles in the first half of the season than usual, sometimes filling the hole but not finishing.
The first time the balance issues came to light was several days after a Week 7 loss at the New York Giants. Fletcher underwent numerous tests from team doctors and a neurologist over the course of several days.
"It wasn't a situation where I was wobbly or anything, but just every now and then, I had a little sway," Fletcher said. "I would notice it, but nobody else would notice it."
He didn't tell the team earlier because he was still able to play. Fletcher said he told them after the Giants game because he also suffered a hamstring injury.
"Players sometimes run to the trainers' room too much," Fletcher said. "You get a hangnail and you run to the trainer. You get a sprained finger, you run to the trainer. For me, I have the mentality if you can go out and play you don't need to run to the trainers' room about every little thing.
"Looking back, I should have told the team about that a lot sooner because it was something that was taken care of immediately. That's the only regret I have about the situation."
Fletcher's play improved after doctors took care of the issue, which they told him stemmed from an irritation in his neck. He intercepted four passes during the Redskins' seven-game winning streak to close the season and missed fewer tackles, despite nursing a badly sprained ankle.
"In my mind, I was like, 'Man, what is going on with me?'" Fletcher said. "I knew I didn't have a concussion, but I'm wondering what's really going on. You're concerned about your future. I'm seeing all these former players, some of the deals they have going on. I knew my neck had a little something going on.
"So you're not excited about throwing your neck up in there making tackles, having a little irritation in there. Once I got that taken care of, I was able to relax from a mental standpoint."
Fletcher reiterated what he told Sports Illustrated in an article out this week, that he last had lingering effects from a concussion while playing for John Carroll University. He also revealed his concussion for the first time publicly in the SI article.
With hindsight, Fletcher said he has suffered concussions throughout his career, based on how they're now being defined. He also said he probably suffered a concussion or two during pickup basketball games when he was younger. But when he suffered the mild concussion last summer, he wanted to keep it quiet.
"I'm an old-school player," Fletcher said. "I'm not going to tell everything about what I have going on. It's just the way I am. If you play football, you have things that bother you all the time. If I told you everything that's bothering me, you would be writing a story every day about what's going on. I don't believe in giving an opponent any prior knowledge of what is affecting me. I don't have to tell, so I didn't tell."
There are no injury reports in the preseason, so teams don't have to disclose injuries.
Fletcher said the neck issues did not leave him in jeopardy of ending his streak. Rather, it was his hamstring and ankle that left it in danger of ending. But he did say as he gets older that he worries about his health.
"But I signed up for this," he said. "No one makes me play this game. I fell in love with football when I was probably 5 or 6 years old. Would I change anything? Not really. You pray for the best as far as the situation down the line.
"At the end of the day, we have to be smart as a player and protect ourselves from ourselves. I've been guilty of needing them to protect me from me. I don't tell them everything that's going on with me from an injury standpoint. I like what the league is doing from that standpoint."