Kirby Lee-USA TODAY Sports

The NFL says 37 different players tested positive for COVID-19 on Monday, the league's worst day for COVID diagnoses since the pandemic first disrupted operations in March 2020. Rams cornerback Jalen Ramsey, Giants wide receiver Kadarius Toney and Chiefs wide receiver Josh Gordon were among the players -- 26 on active rosters and 11 on practice squads -- to land on COVID reserve as a result, while a Washington Football Team staffer also tested positive for the Omicron variant of COVID.

The Washington staffer, designated as a Tier 3 employee because of a lack of required contact with players, has the first known case of the Omicron variant, NFL Media reported. This person had minimal contact with other staff members, ESPN's Adam Schefter added Monday, but will remain quarantined as a result of their positive test. The NFL has also instituted a vaccine booster mandate as of Monday, asking that all employees who've already been fully vaccinated receive booster shots by Dec. 27.

Among the 36 players added to COVID reserve are Ramsey, Gordon, Toney, Bears defensive end Mario Edwards, Cowboys wide receiver Cedrick Wilson, Texans linebacker Kamu Grugier-Hill, Chargers offensive tackle Rashawn Slater, Rams tight end Tyler Higbee and offensive lineman Rob Havenstein, Dolphins running back Phillip Lindsay, Vikings running back Alexander Mattison, Eagles wide receiver Quez Watkins and Washington defensive lineman Jonathan Allen.

All players who test positive for COVID-19 or land on reserve/COVID-19 are forbidden from returning to work until either logging two negative tests 24 hours apart (if vaccinated) or proving asymptomatic after 10 days of isolation.