Brown has tested positive for the virus, sources told ESPN's Adam Schefter.
"Kevin and A.B. are both on the COVID list. With A.B., we've got plenty of guys with a proven track record at that position," Arians said, pointing to their depth at wide receiver with Scotty Miller and Tyler Johnson. "Kevin will be missed as far as special teams, but we've got some young guys ready to roll."
Arians said Minter and Brown technically still have a chance to play Sunday, but the team is preparing as if they won't be available.
Brown, like every one of his teammates and all members of the Bucs' coaching staff, is fully vaccinated, and per NFL rules, needs two negative tests 24 hours apart to return, as long as he is asymptomatic.
Players who are vaccinated are not subject to the mandatory 10-day quarantine as unvaccinated players.
Brown's 138 receiving yards through two games is second-most on the team this season, and he's arguably the Bucs' most versatile route runner -- he can go deep but also is extremely productive using his suddenness inside.
Last year's team moniker was "beat the virus," and Arians has largely attributed losing only four starters to COVID-19 -- for a total of six games -- with winning the Super Bowl.
The Bucs hit the road this week for one of the more challenging parts of their schedule. They take on the Los Angeles Rams on Sunday, and then next week, they'll travel to Foxborough, Massachusetts, to take on the New England Patriots.
The Bucs lost to the Rams 27-24 last season, with the Rams limiting the Bucs to just 209 passing yards, among the lowest of their season.