The contests are being rescheduled "in order to ensure the health and safety of players on both teams" as some members of the Grizzlies undergo contact tracing while other Memphis players are unavailable, according to the league.
The Grizzlies' Wednesday game against Portland was also postponed.
Memphis' recent spate of shelved contests began with last Friday's matchup with the Minnesota Timberwolves. The Grizzlies' next game against the Philadelphia 76ers went on as scheduled, but the 76ers' next contest after that was postponed due to contact tracing.
Memphis played the Phoenix Suns on Monday.
The NBA is erring on the side of caution with a seemingly isolated COVID-19 exposure within the Grizzlies, sources told ESPN's Adrian Wojnarowski. The approach is similar to the NFL's strategy, reports Wojnarowski.
Twenty NBA contests have now been postponed this season due to COVID-19 protocols.