RICHMOND — The Washington Football Team ended its week of training camp in Richmond by placing two more players — right guard Brandon Scherff and offensive tackle David Sharpe — on the reserve/covid-19 list, creating greater concern about the team’s vaccination rate and potential for an outbreak.

Washington has six players — including wide receiver Curtis Samuel, offensive tackle Cornelius Lucas, defensive tackle Matt Ioannidis and cornerback Chris Miller — on its covid-19 list, which, as of Saturday morning, was the second most in the NFL behind only the Arizona Cardinals (nine).

Coach Ron Rivera, who underwent cancer treatment last year for squamous cell carcinoma, has expressed his frustration with the team’s vaccination rate and said Saturday he hopes his own circumstances will sway players who have been reluctant to get immunized.

“I think just making the statement that I’m immune deficient hopefully is part of their conversation, part of their thought process,” he said. “It is a personal decision, and we just hope that we can get more guys vaccinated. I’ve tried to broach it with a lot of our players, talk with a lot of our guys that have it. Again, it’s a personal thing. But hopefully we can sway them.”

Last season, Washington was among the teams with the fewest players to test positive. Only two were placed on the covid-19 list during the regular season, and both — Ioannidis and running back Javon Leake — were not on the active roster at the time. Tight end Logan Thomas also tested positive at the start of 2020 training camp, and wide receiver Antonio Gandy-Golden said he had the virus that spring. Neither missed any time during the regular season.

Rivera said he has spoken to many of Washington’s unvaccinated players in an attempt to understand their reluctance to get immunized and to relay any information he has learned about the vaccines. In June, during minicamp, he elicited the help of Kizzmekia S. Corbett, an immunologist and leading coronavirus researcher, to speak to players and answer questions.

“I just think it’s a matter of these guys being educated and understanding because it’s fair when you sit down and talk to these guys and listen to them and listen to their true concerns,” Rivera said. “I think some guys just don’t know, and I’ve gotten a sense that there are a few guys that have dug in so hard, so much that they’re not going to back down. So that’s the part to me that’s concerning because I care about all these guys, I really do.”

Washington’s player vaccination rate — which includes those in the process of getting vaccinated as well as those fully immunized — has been among the league’s lowest in recent months. On Monday, the team had 60 percent of its players at least partially vaccinated. That figure improved during the week in Richmond, but it’s unclear exactly how much.

According to a person with knowledge of the situation, Washington no longer has the lowest rate in the league, with at least 70 percent of its players at least partially vaccinated as of Saturday afternoon.

Of the 32 NFL teams, 22 had more than 90 percent of their players vaccinated, and among all players, 89.4 percent are vaccinated — well above the national rate of 57.5 percent.

Neither Washington nor the league distinguishes publicly which players test positive for the coronavirus and which ones are placed on the list because they are close contacts. According to mandates agreed upon by the NFL and NFLPA, if players are fully vaccinated and test positive, they can return to practice if they have two negative tests taken 24 hours apart. But unvaccinated players who test positive must isolate for at least 10 days, and those considered “high risk” close contacts must quarantine five days and undergo daily PCR testing.

The absences could have more severe consequences for teams in season, when quarantines force roster shuffles and could require the league to reschedule a game because of an outbreak. In a memo sent to teams in mid-July, the league reminded that if a game cannot be rescheduled, the team responsible for the outbreak will forfeit and players will not get paid.

“And that’s part of the problem,” Rivera said. “I mean, to be very honest, that’s going to make things difficult and that’s the thing we have to be aware of. It makes it difficult in terms of everybody working together.”

Rivera posed to his players a what-if scenario: What if Saturday had been Sept. 12, and the team was about to face the Los Angeles Chargers in its season opener? If Scherff and Sharpe were, at minimum, flagged as close contacts, they would have to miss two games because Washington hosts the New York Giants the following Thursday night.

“It brings the reality of what the rules are, and I hope it helps,” he said. “But, again, these young men have to make their decisions.”

The disadvantages extend to training camp, where many players are fighting for roster spots.

The team’s first of three preseason games is Aug. 12 at New England. Should a player test positive Monday or thereafter, he would miss at least one game because of the required 10-day quarantine.

Rivera is hopeful more players will get vaccinated in the coming days and said some even have appointments scheduled for Sunday, after the team returns to Ashburn for the remainder of camp.

“I know it’s improved,” he said of the team’s vaccination rate. “It’s trending in the right direction, and hopefully we’ll continue to have it rise for us.”