By Amy Tennery
(Reuters) - Major League Baseball (MLB) postponed Saturday's game and Sunday's double-header between the St. Louis Cardinals and Milwaukee Brewers after initial rapid tests showed another player and "multiple" staff on the Cardinals may have COVID-19.
MLB is scrambling to keep its coronavirus-shortened season on track after numerous games were postponed due to positive test results, with an outbreak on the Miami Marlins injecting uncertainty just days after the delayed, truncated season began.
The league had already rescheduled Friday's game between Milwaukee and St. Louis after two Cardinals players tested positive.
Brewers center fielder Lorenzo Cain opted out of the rest of the 2020 season, the team said on Saturday, though it did not specify why.
"We fully support Lorenzo's decision, and we will miss his talents on the field and leadership in the clubhouse," Brewers President and General Manager David Stearns said in a written statement.
The Boston Red Sox confirmed on Saturday that 27-year-old pitcher Eduardo Rodriguez would miss the rest of the season after developing myocarditis, an inflammation of the heart, after his COVID-19 diagnosis.
"We were optimistic that it would resolve in short order and that we would be able to progress him back to pitching. As we continued to monitor it, it has not resolved. It is still there," Red Sox Chief Baseball Officer Chaim Bloom told reporters.
"We need to make sure we're taking care of him. This is not something to mess around with."
The Red Sox expect Rodriguez to return next season.
The league said on Friday that there were 29 new positive tests - 20 players and nine staff members - in the past week, comprising 0.2% of all tests taken in that period.
The Marlins have been quarantined in Philadelphia since Sunday after numerous members of the club tested positive after playing against the Phillies, who head to the Bronx to play the Yankees on Monday.
Three Phillies staffers had tested positive for COVID-19, MLB said, though two of those reports turned out to be false positives.
(Reporting by Amy Tennery; Editing by Hugh Lawson and Paul Simao)