CINCINNATI (AP) — Reds players and staff were tested for COVID-19 again Sunday as Major League Baseball tried to determine if more than one Cincinnati player has been exposed to the novel coronavirus.

The last two games of a series between the Reds and Pittsburgh Pirates were postponed Saturday after the player tested positive. Both teams had days off Monday, creating an opportunity for a makeup doubleheader, but MLB was waiting on further testing.

The Pirates worked out Sunday at Great American Ball Park and returned to Pittsburgh, where they will start a three-game series against the Cleveland Indians on Tuesday.

Cincinnati is scheduled to go to Kansas City for a two-game series starting Tuesday night. The Reds then are scheduled to head to St. Louis for four games, followed by four in Milwaukee.

The Reds expect results of their latest tests on Monday when a decision will be made whether they travel to Kansas City.

The Reds are the third MLB team to have games postponed because one of its players tested positive for COVID-19, joining the Marlins and the Cardinals.

As the Reds gathered on the field to celebrate an 8-1 win over the Pirates on Friday night, a coach took center fielder Nick Senzel aside for a discussion. Senzel was upset as he walked off the field. Manager David Bell declined to discuss it after the game other than to say it was a “personal” situation and more information will be forthcoming.

Under medical privacy rules, teams aren’t allowed to identify players who test positive for COVID-19.

The Reds’ Matt Davidson confirmed that he tested positive during the opening series of the abbreviated, 60-game season, forcing him onto the injured list. After his return, Davidson said subsequent tests were negative, an indication that the original test yielded a false positive.

Three other Reds — Joey Votto, Mike Moustakas and Senzel — have missed games after feeling sick, but tested negative for the coronavirus and rejoined the team.