Ron Rivera first noticed it while shaving. Lodged in his neck was a lump that, at the time, didn’t seem too concerning. He has played or coached a violent sport for the better part of four decades, so what was a little bump?

When he awoke the next morning, he felt a strain in his neck that he attributed to a pulled muscle, so he treated it as such. When it didn’t go away, he reported it to Anthony Casolaro, a physician for the Washington Football Team, and later underwent testing to find out the little lump was a much bigger deal.

On Thursday night, the team announced Rivera, 58, had been diagnosed with squamous cell carcinoma in a lymph node. In a statement, the team noted the cancer was detected in the early stages and is “considered very treatable and curable.” He is expected to make a full recovery, and the hope until then is that he can continue to work, balancing his treatment with an ever-expanding role as the team’s head coach and culture-fixer.

“What’s going to be the tough part most certainly will be just trying to manage time,” Rivera said in an interview posted on the team’s website Friday. “I hope to do these treatments and not have them interfere with football. It’s been recommended that I continue to work — work at a good pace, a smart pace, listen to what the doctors tell me, follow the protocols.”

Rivera said his treatment plan is still being mapped out, but he is expecting 35 days of treatment — five times per week for seven weeks — that includes proton therapy and “some other stuff,” he said.

Before the news became public Thursday, Rivera informed his players, something he had been planning to do for weeks. He wanted to be sure about his prognosis, and he wanted to time the conversation so his players were shielded, as much as possible, from any accompanying drama. So he told them the day before they had a scheduled day off from practice, allowing them to avoid immediate questioning from the media and return their focus to football.

“I had a meeting before with the players, before we went to work out [Thursday], and I kind of left them with a little bit of a message at the end, and that’s basically: ‘You can have everything taken away from you but one thing, and that’s your right to choose how you’re going to approach things in your life. They can’t take away your opportunity to choose your attitude,’ ” Rivera told the team website. “I left that with the players, and when I brought them back in, I gave them the news and said: ‘Look, I still control my attitude. I control my outlook in the way I approach this.’ I just wanted to share that message with them. I think that helped them. I think it helped me more so than anything else.”

In the hours that followed, Rivera said he received numerous messages from players. The one that stood out the most was from Alex Smith, the 36-year-old quarterback who recently returned to football activities after suffering a compound right leg fracture in November 2018.

“A guy like Alex Smith, for having gone through what he has … I truly do find strength in people like that,” Rivera said. “Especially a young man like Alex.”

On Friday, Rivera talked to his coaches — including his coordinators, whose jobs may change if he has to step away at any point. “Plan B,” as was mentioned in the team’s statement Thursday, is Jack Del Rio, Washington’s defensive coordinator, who has 12 seasons of experience as an NFL head coach and went through a similar situation at one of his previous stops.

In 2013, when Del Rio was the Denver Broncos’ defensive coordinator, head coach John Fox missed four games after undergoing aortic valve replacement surgery. Del Rio took over in the interim, retaining his duties as defensive coordinator, and the team went 3-1. By the time Fox returned, the Broncos had moved into first place in the AFC West on their way to a spot in the Super Bowl.

Rivera told the team website that his doctors encouraged him to continue working. “They did say, too, ‘But, there will be a time you may have to step away for a day or two or maybe a week or two,’ ” he recalled. In talking to Del Rio, the two agreed it’s paramount that business continue as usual and that “everybody does their job.”

“It’s really my messaging, but Jack may be the one that has to step up front and do it,” Rivera said. “We talked about that; we’re prepared to do that. I think, again, the one thing, too, is we’ll put a little bit of the onus on the players. This is a little something that as a coach you always hope that the players buy in and they take ownership of situations, circumstances. This might be a great test to find out exactly where we are in this process of developing this football team: Are these guys ready to step up and take ownership of something?”

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