DAVIE, Fla. -- Miami Dolphins veteran quarterback Ryan Fitzpatrick has tested positive for COVID-19 and will be unavailable for Sunday's regular-season finale against the Buffalo Bills, a source confirmed to ESPN.

He was placed on the reserve/COVID-19 list on Thursday afternoon, the team announced.

The Dolphins and the NFL have conducted initial contact tracing with no high-risk close contacts determined as of Thursday afternoon, a source told ESPN, but that process will continue. Fitzpatrick practiced fully Wednesday and wasn't listed on the injury report, but he didn't practice Thursday afternoon, indicating that the positive COVID-19 test was a recent surprise.

Dolphins safety Eric Rowe said that coach Brian Flores informed the team about Fitzpatrick's status during a Zoom meeting.

"It hurts. He's a leader on our team. He brings energy," Rowe said. "I'm sure it's worse for him because he loves the game and no one wants to catch COVID. With that, you have to push forward.

"COVID is a real-deal thing whether you don't have symptoms or you do. Just praying he doesn't have symptoms or he didn't pass it to his kids."

Rookie Tua Tagovailoa is the Dolphins' starting quarterback, but Fitzpatrick has been called on twice in the fourth quarter to play what Flores compared to a "ninth-inning reliever" role. Fitzpatrick led the Dolphins to a 26-25 comeback win over the Las Vegas Raiders on Saturday after a 34-yard heave coupled with a 15-yard face mask penalty set up the game-winning field goal.

The Dolphins signed Jake Rudock to the 53-man roster Thursday, and he is expected to be Tagovailoa's backup Sunday. Tagovailoa, Rudock and practice squad quarterback Reid Sinnett practiced fully Thursday.

In addition, linebacker Elandon Roberts was placed on injured reserve and receiver Kirk Merritt was added to the roster as a COVID-19 replacement for Sunday's game.

NFL Network first reported Fitzpatrick's positive test.

The Dolphins would clinch a playoff berth with a win over the Bills. They could still make the playoffs with a loss but would need a loss from either the Cleveland Browns (vs. a Steelers team resting key starters), Indianapolis Colts (vs. Jaguars) or Baltimore Ravens (vs. Bengals). The Bills, who have clinched the AFC East but can earn the No. 2 (vs. No. 3) seed based on Week 17 results, have been coy on whether they will play their starters.

Fitzpatrick, who has never made the playoffs in his 16-year career, could be in jeopardy of missing the Dolphins' first playoff game if they make it. Any asymptomatic player who tests positive for COVID-19 must wait at least 10 days before rejoining the team.

That means the earliest Fitzpatrick could return to the team is Sunday, Jan. 10, and only if he travels separately from the team via private transportation to participate in the game. There will be three playoff games on Saturday and three on Sunday for wild-card weekend this season.

Fitzpatrick, 38, is 4-3 as a starter this season, throwing for 2,091 yards with 13 touchdowns and eight interceptions.