OKLAHOMA CITY (CBS/AP) –The Oklahoma City Thunder’s scheduled home game Sunday night against the Philadelphia 76ers has been postponed. Because of ongoing contact tracing within the 76ers, the NBA said the team does not have the league-required eight available players to proceed with the game.

According to PhillyVoice’s Kyle Neubeck, there are no new COVID-positive tests for the Sixers.

ESPN’s Adrian Wojnarowski reported that Memphis Grizzlies center Jonas Valanciunas is in the NBA’s health and safety protocol and will be out Monday.

Sunday’s Sixers-Thunder game was the 13th game called off since Jan. 10 because of virus issues, a span in which the NBA and the National Basketball Players Association have stiffened protocols and even added testing with hopes of keeping the season going without much in the way of additional problems.

That 76ers-Thunder determination was made about 90 minutes before the planned start time. The 76ers played in Memphis on Saturday night, losing 106-104 in a game where Valanciunas played 20 minutes.

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The Grizzlies said he would be unable to play Monday against Phoenix because of the league’s protocols — which could mean many different things including a positive test, an inconclusive test or possible exposure to someone who is positive for COVID-19.

It is the second time this month that the protocols have flagged Valanciunas. He was pulled at halftime of Memphis’ game against Brooklyn on Jan. 8 because of some sort of virus-related issue, but was back on the court for the Grizzlies’ next game Jan. 11 against Cleveland.

“False alarm. Everyone around me is healthy and I am cleared to get back on the court,” Valanciunas wrote on Instagram last week.

Sunday’s postponement is the first for Philadelphia and Oklahoma City since this latest wave of virus issues in the NBA started earlier this month, and raised the total to 18 teams who have seen at least one game called off since Jan. 10. The Thunder also had a game in Houston called off Dec. 23 because the Rockets did not have enough players eligible to play, in large part because of contact tracing issues.

Cleveland’s game in Washington on Sunday also was called off, as was the planned rematch between the clubs on Monday. Those decisions were made last week when the Wizards said nine players — six with positive COVID-19 tests and three others snagged by contact tracing — were not cleared to be on the floor.

A positive for the Wizards: their six healthy players were able to return to the team practice facility Sunday for 1-on-0 workouts. The earliest Washington will play is Wednesday at Charlotte. If that game happens, it will be the end of a nine-day break for the Wizards.

Phoenix’s game in Memphis on Monday is scheduled to be the Suns’ first game in a week. Minnesota, which had a game Friday called off after Karl-Anthony Towns revealed he tested positive, is scheduled to play Monday in Atlanta. Ricky Rubio has also been ruled out by the Timberwolves for virus-related reasons.

A number of other NBA players remain ineligible to play because of the league’s protocols, including Miami’s Jimmy Butler and Avery Bradley — both of whom will miss a fourth consecutive game Monday when the reeling Heat play host to Washington. And Jayson Tatum missed another game Sunday for Boston, also with “protocols” cited as the reason, and the Celtics were beaten by the New York Knicks.

(© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)

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