LAKE BUENA VISTA, Fla. (CBS/AP) — Major League Soccer postponed a match between Toronto FC and D.C. United shortly before it was scheduled to begin Sunday morning because of one unconfirmed positive test and one inconclusive test for the coronavirus.

The postponement will have an impact on other matches in the tournament, including one for the New England Revolution.

READ MORE: 'It Looked Like Niagara Falls,' Massive Water Main Break Floods Part Of Beacon Hill

The unconfirmed positive test was for a D.C. United player, while a Toronto player returned the inconclusive test. Players and staff are tested the day before each game during the MLS is Back tournament. Because of the positive and inconclusive tests, the league’s protocol for the tournament called for both teams to undergo another set of testing.

The league announced Sunday night that the match would be rescheduled for Monday with a 9 a.m. EDT kickoff after all players on both teams had tested negative during the additional round of testing. The player who tested positive and the player with the inconclusive test will have another round of testing and will not play Monday.

Both teams had already announced their starting lineups for the match when it was called off shortly before its scheduled 9 a.m. EDT kickoff.

READ MORE: Green Line Operator Put Train In 'Full-Power Position' Before July Crash, NTSB Report Finds

The teams also had their second matches in the tournament pushed back by one day. Toronto will now face Montreal on Thursday and D.C. United will play New England on Friday.

The Revolution had originally been scheduled to play D.C. United on Thursday, but will wait another day as a result.

The postponement is the latest hiccup for the tournament, which has already had two teams drop out because of a spate of COVID-19 cases. FC Dallas and Nashville were both withdrawn earlier this week, reducing the tournament to 24 teams. FC Dallas had 10 players and one coach test positive for the virus. Nashville had nine players test positive.

MORE NEWS: Former Fall River Mayor Jasiel Correia Sentenced To 6 Years In Prison

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