AP photo by Wade Payne / Tennessee Titans cornerback Kristian Fulton is congratulated by free safety Kevin Byard after Fulton intercepted a pass against the Jacksonville Jaguars on Sept. 20 in Nashville.

NASHVILLE — The Tennessee Titans have heard some of the calls for the NFL to punish them harshly for the team's role in the league's first COVID-19 outbreak, and they have some words of caution after firsthand experience.

It's still a pandemic. And testing, even as much as the NFL does, is not perfect.

Titans quarterback Ryan Tannehill said Saturday it's been a roller coaster as people with no symptoms test positive while others with full-blown symptoms receive consecutive negative tests on multiple days. He noted everyone had said from the beginning that testing would not prevent the virus from being spread.

"It was really eye-opening, and just the fact of we really don't know, so we have to treat everyone as if they have the virus, unfortunately," Tannehill said. "I feel like we probably lost faith in the testing system just through everything we've been through over over the past week and a half."

As the Titans' outbreak grew to 23 with 21 positive tests returned since Sept. 29, safety Kevin Byard said he heard calls for Tennessee to forfeit games as the NFL rescheduled its Week 4 home game against the Pittsburgh Steelers to Oct. 25, which also led the league to move the Steelers' game against the Baltimore Ravens to Nov. 1.

The Titans (3-0) hope now to host the Buffalo Bills (4-0) on Tuesday night.

"If anybody went into the season thinking that there weren't going to be a couple of positive tests or outbreak somewhere of all 32 teams, I think that was kind of foolish to think," Byard said. "I mean, obviously, we wasn't trying to be the team that had the outbreak. We're not trying to get COVID-19."

What the Titans weren't talking about was just how this outbreak occurred, at least not until the NFL and NFL Players Association speak first.

"We've been completely transparent with the NFL, the NFLPA throughout this entire process, and we're going to wait for their summary before commenting further on any of those discussions," coach Mike Vrabel said.

The Titans and the New England Patriots had no positive COVID-19 tests Saturday, allowing both teams to return to their facilities. The Patriots had not been at their facility since cornerback Stephon Gilmore's test came back positive Wednesday.

The Titans haven't played since Sept. 27, when they beat the Minnesota Vikings 31-30 in Minneapolis, and the NFL forced them to close their facility two days later before they could begin practicing for the scheduled game against the Steelers. Rain forced the Titans inside for practice Saturday.

Vrabel said every player and coach was made available to talk with the officials running the investigation of how the outbreak occurred.

One result is that the Titans have moved 30 lockers from their locker room to their indoor practice field. Vrabel said the team made adjustments to the way meals are taken, and any in-person meetings for coaches will be held at the indoor field.

Both Tannehill and Byard declined to comment when asked about player workouts Sept. 30, a day after the NFL closed the Titans' facility, saying they had been "transparent" with the review done by the NFL and union. Vrabel said they're very confident in how they've handled their end of the review.

"I'm sure that this won't be the first time that somebody says something bad about us or one of our players or one of our coaches or me or our team," Vrabel said.

New England coach Bill Belichick said the Patriots won't be making any decisions or long-range plans until they have more information. His plan was to get through Saturday with a practice planned to maximize their time back on a field. Their Week 5 home game with the Denver Broncos was moved from Sunday to Monday.

"One thing we've learned this year is that we all have to be able to adapt to changes and adjustments and make adjustments, so that's what we're going to do," said Belichick, whose team had its game pushed back a day for the second week in a row.

The Patriots, playing without quarterback Cam Newton after he tested positive, lost 26-10 to the Kansas City Chiefs this past Monday.

Tennessee has gone without a positive test for the fourth time in six days with the latest results, a person familiar with the situation told The Associated Press. The person spoke on condition of anonymity because neither the NFL nor the Titans announced the latest results.

Now that both the Titans and Patriots are back at work, the question is whether either team gets any of the players currently on the COVID-19 reserve list back for their next game. The NFL and union updated the protocol for when players who test positive can return to play, depending on whether the player experienced symptoms.

Neither Gilmore nor Newton practiced Saturday. Belichick, speaking before practice, would not say whether either would play Monday.

Vrabel said the Titans might get some players back if they're cleared to return, including long snapper Beau Brinkley. The Titans have possible replacements going through the testing protocol in case Brinkley isn't back for a team that won each of its first three games by a field goal inside the final two minutes.

Later Saturday, the Titans activated offensive lineman Isaiah Wilson, their first-round pick who had been out since Sept. 6, and defensive back Greg Mabin, a member of the practice squad, off the COVID-19 reserve list.