The Buffalo Bills announced Saturday that tight end Dawson Knox and three other players have been placed on the reserve/COVID-19 list after testing positive.

Knox was already listed as out for Sunday's game against the New York Jets with a calf injury. In their statement, the Bills announced that fellow tight ends Lee Smith, Tommy Sweeney and Nate Becker have also been placed on the reserve/COVID-19 because of their close contact with Knox:

Smith, Sweeney and Becker are all out for Sunday's game as well, although Sweeney was already on the PUP list and Becker is a practice-squad player.

Knox's positive COVID-19 test is the first confirmed for the Bills this season, and it comes on the heels of back-to-back games against teams that had multiple cases.

The Tennessee Titans had to have their Week 4 game against the Pittsburgh Steelers postponed because of a COVID-19 outbreak within the organization that yielded more than 20 cases, and their Week 5 game against the Bills was moved from the Sunday to the following Tuesday.

Buffalo then faced the Kansas City Chiefs in Week 6 on Monday in a game moved from the previous Thursday after the repositioning of the Bills vs. Titans game. Kansas City previously placed practice-squad quarterback Jordan Ta'amu and fullback Anthony Sherman on the reserve/COVID-19 list.

Knox hadn't practiced during the week because a calf injury suffered in Week 5 against Tennessee. The second-year tight end missed last week's game with the calf ailment and Week 3's game against the L.A. Rams with a concussion.

In four games so far this season, including three starts, the 23-year-old Knox has caught six passes for 93 yards. As a rookie third-round pick last season, Knox made 28 grabs for 388 yards and two touchdowns.

With Knox, Smith, Sweeney and Becker all on the reserve/COVID-19 list, the only healthy tight ends on the roster who are eligible to play Sunday are Tyler Kroft and Reggie Gilliam.

Kroft has appeared in all six games for the Bills this season and made two starts. The former Cincinnati Bengals tight end has six catches for 43 yards and two touchdowns.

Gilliam is an undrafted rookie and converted fullback who has one catch for one yard and one touchdown in 2020.

Buffalo called wide receiver Duke Williams up from the practice squad Saturday, which suggests the Bills could attempt to use the 6'3", 225-pound wideout in a de facto tight end role against the Jets.

Provided Sunday's game goes on as scheduled, the AFC East-leading Bills will put their 4-2 record on the line against the winless Jets at MetLife Stadium in East Rutherford, New Jersey.