BOSTON (CBS) — Just when it seems like the Celtics roster may become whole again, COVID-19 rears its ugly head. On Monday, star forward Jayson Tatum was added to the league’s Health & Safety Protocol, leaving Boston without its top player for the foreseeable future.

Tatum is now the eighth player to be ruled out for Monday night’s game against the Timberwolves in Minnesota because of Health & Safety Protocol. The Celtics will also be without rotation players Dennis Schroder, Josh Richardson, Enes Freedom, and Aaron Nesmith, along with Bruno Fernando, C.J. Miles and Justin Jackson.

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Miles and Jackson were just signed to hardship contracts last week to help Boston fill out its roster. The C’s also signed Joe Johnson last week, and added Al-Farouq Aminu and Norvel Pelle ahead of Saturday’s loss to the Bucks in Milwaukee.

Losing Tatum for any period of time is a huge blow for the Celtics, who sit at a disappointing 16-17 on the season. Tatum has played in every game this season and is averaging 25.6 points and 8.6 rebounds per game, both of which lead Boston.

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Tatum missed time last season after testing positive for COVID-19 and struggled to regain his wind upon his return, requiring the use of an inhaler. He said ahead of the season that he was vaccinated against COVID-19.

He is now out for at least 10 days, unless he can produce two negative COVID-19 tests 24 hours apart. Should he miss the full 10 days, Tatum will miss Monday’s road game against the Timberwolves, home games this week against the Los Angeles Clippers, Phoenix Suns and Orlando Magic, a home game against the San Antonio Spurs next Wednesday, and the first leg of a home-and-home against the New York Knicks.

While Tatum is now out of the mix, the Celtics may be getting a pair of big men back on Monday night. Al Horford was not listed on Boston’s injury report on Sunday night and appears set to make his return after missing five games with COVID-19. Horford was listed as questionable for Saturday’s loss in Milwaukee, and was ultimately ruled out for that contest due to conditioning.

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Grant Williams is also set to return Monday night, upgraded to “available” Monday afternoon after his stay in protocol. Staff