Ahead of the N.C.A.A. tournament, the biggest stage in men’s college basketball, Louisville Coach Chris Mack and his players have the role of understudies: They will be the first replacements should a team from a multiple-bid conference be unable to play this week because of coronavirus issues.
Virginia, the tournament champion in 2019, and Kansas withdrew from their conference tournaments last week because of virus protocols. They earned at-large berths to the national tournament in Indiana, but whether they will be able to play remains an open question.
Alternates will be able to fill slots vacated by teams with coronavirus issues through Tuesday at 6 p.