Two more NBA games were postponed by the league on Monday due to Covid-19 and contract tracing issues, bringing the total to four in the virus-shortened 2020-21 season.

The New Orleans Pelicans game at Dallas on Monday and the Boston Celtics game Tuesday at Chicago were both delayed over unspecified health and safety protocol issues.

The league also said it would meet with the National Basketball Players Association on Monday about possible modifications in the joint safety protocols.

There has been concern expressed by coaches about the health and safety of players being forced into playing unusually high numbers of minutes due to depleted rosters being forced to take the court.

The latest postponements will mark three consecutive days of lost games for the NBA after Miami's matchup on Sunday against the Celtics in Boston was called off because the Heat were unable to field a minimum eight players due to Covid-19 issues.

The Celtics had been reduced to the minimum eight players by virus issues with seven players missing due to the virus or contact tracing.

The Heat were still scheduled to play on Tuesday night in Philadelphia, where the 76ers had only a minimum eight available players, just seven of them healthy, for a home loss Saturday to Denver.

The South Florida Sun-Sentinel reported that the Heat's available players would travel from Boston to Philadelphia while players deemed at risk through contact tracing would be flown to Florida to quarantine.

The NBA announced on Monday it has postponed scheduled games between New Orleans and Dallas on Monday and Boston and Chicago on Tuesday due to Covid-19 issues
The NBA announced on Monday it has postponed scheduled games between New Orleans and Dallas on Monday and Boston and Chicago on Tuesday due to Covid-19 issues NBAE / Getty Images / Garrett Ellwood

The first NBA game to be postponed this season due to Covid-19 issues was on December 23 between Oklahoma City at Houston.

Dallas has three players listed as out due to the NBA Covid-19 protocols -- Jalen Brunson, Josh Richardson and Dorian Finney-Smith -- and Maxi Kleber listed as questionable for the same reason.

Scott Tomlin, the Mavericks' vice president of basketball communications, told the Dallas Morning News that the team would have had at least eight players available on Monday, but the league chose to postpone the contest "to ensure the health and safety of players, coaches and other personnel" as contact tracing continues.

NBA commissioner Adam Silver said before the season started on December 22 that the league, which completed the disrupted 2019-20 season in a quarantine bubble in Orlando, Florida, expected disruptions as it forged ahead in teams' home markets with coronavirus still surging.

"We do anticipate there will be bumps in the road along the way," Silver said in December, adding that's why the schedule for only the first half of the season had been released.

"We know it's possible we may have to reschedule games along the way," he said.

Philadelphia coach Doc Rivers said Saturday he trusted the procedures the league had put in place to limit spread of Covid-19, but he said losing so many players to contact tracing posed a danger to those remaining with increased minutes on the floor, wear and tear and the push to perhaps play through injury.

"That's long-term health with the accumulation of games," he said. "So I'm actually more concerned about that than I am actually about Covid."