McKenzie tweeted out a picture of the letter he was sent by the NFL detailing multiple documented violations of the protocol. He said in a subsequent tweet that he was fined $14,650.
"They got me!" McKenzie wrote. "@NFL you win!"
Beasley did not disclose how much he was fined, only saying on Twitter that he was disciplined for not wearing a mask for "literally 5 steps" from the entry door to the locker room after wearing it "that whole day."
"It's unfortunate when players get fined," Bills coach Sean McDermott said Thursday. "That being said, these rules have been agreed upon and in place and well-communicated for some time. And so it's important for us that we focus on being safe and healthy -- that's No. 1 and that's always been No. 1 -- and then No. 2 is doing our best to stay focused on the goal and the purpose of why we're here -- which is to win football games."
According to the league's letter, McKenzie's discipline comes after he failed to wear a mask in the team facility on multiple occasions on Wednesday -- once while walking through the indoor fieldhouse into the training room and again in the meeting area of the weight room "while gathered near other players after the offensive meeting."
In addition to those violations, the league said it sent a written warning to him on July 27 saying that future violations would result in "increased discipline, including for conduct detrimental."
Under the NFL's COVID-19 policy, unvaccinated players are required to wear a mask throughout the team facility, which the league reminded McKenzie of in its letter Thursday.
"Your conduct is expressly prohibited by the Protocols," the NFL told McKenzie. "Again, your conduct potentially compromised not only your safety, but also the safety of others, as well as the league's ability to ensure that your club's training camp is conducted in a safe manner."
The violations come after the Bills sent six players home Tuesday who were deemed close contacts to a vaccinated staff member who tested positive for COVID-19. Beasley, Gabriel Davis, Star Lotulelei and Vernon Butler were all designated close contacts by the NFL and must remain away from the facility for five days, per NFL policy. The Bills also sent Matt Milano and A.J. Klein home for precautionary reasons, but neither were designated close contacts by the NFL and were allowed to return to practice Wednesday.
Beasley has been vocally opposed to the NFL's protocols for vaccinated and unvaccinated players and responded in support of McKenzie on Thursday.
"Don't worry they got me too," Beasley tweeted. "But I was wearing a mask when I was in close contact with fully vaxxed trainer who tested positive and still got sent home. So what's the point of the mask anyways?
"Meanwhile I'm here still testing negative and can't come back. Make it make sense."
McDermott said around 81% of the team is fully vaccinated. Buffalo has placed three players on the reserve/COVID-19 list due to positive tests this preseason, including starting left tackle Dion Dawkins -- who was hospitalized for four days as a result of the virus.
"I go back to the personal decision on this thing. I respect our players' positions," McDermott said Thursday. "In my personal opinion, it's right to get vaccinated."
McDermott said there's a fine line between the personal and competitive reasons surrounding players' choices to be vaccinated or not, but he stressed that final roster cuts will not based on players' decisions regarding the matter.
"That [choice of being vaccinated or not vaccinated] will not be a factor in deciding who stays and who goes," McDermott said.