Major League Baseball’s sputtering effort to play in a pandemic took another discouraging turn on Saturday when one St. Louis Cardinals player and three team staffers tested positive for the coronavirus, forcing the postponement of their game in Milwaukee for the second day in a row.
The test results and the postponement were confirmed by two people with direct knowledge who were not authorized to comment because M.L.B. had not made an official announcement.
The Cardinals, who also had two players receive positive tests on Friday, now have six positives in their traveling party and have become the second team, with the Miami Marlins, to experience an outbreak less than two weeks into the truncated M.L.B. season. The Marlins have had 20 people, including 18 players, test positive since last Sunday.
With another Cardinals-Brewers postponement, six teams — comprising 20 percent of the league — have been shut down this weekend for reasons related to the virus. The Marlins and the Phillies have not played since last Sunday, when the Marlins learned of their outbreak before a game in Philadelphia. With those teams out of action, their scheduled opponents for this weekend, the Washington Nationals and the Toronto Blue Jays, have also been off.
The Phillies have had two positive tests (a coach and a clubhouse staffer) since playing the Marlins, but announced Saturday that they had no new positives for the second day in a row. They are scheduled — for now — to play the Yankees for four games this week, but the Marlins are paused indefinitely.
The Marlins’ personnel who tested positive embarked on a bus trip from Philadelphia to Miami on Friday as the team scrambles to make trades and sign free agents to fill out a competitive roster. Isan Diaz, a Marlins second baseman, opted out of the season on Saturday morning.
“This has been a tough week to see so many of my teammates come down with this virus, and see how quickly it spreads,” Diaz posted to Instagram, adding later, “This has been a decision that I have discussed with my family, and I feel it’s the best one for me and my overall well-being.”
The Brewers said Saturday that center fielder Lorenzo Cain had also opted out.
For now, M.L.B. still plans for its teams to play 60 games apiece — or as close to 60 as possible — in a regular season scheduled to end on Sept. 27, before a postseason of four rounds through the end of October. But the complications of travel, and the failure by at least some of the Marlins to adhere to safety protocols on a preseason trip to Atlanta, have put the season in peril.