On what might have been the bleakest day of an exceedingly bleak spring for Major League Baseball, the owners effectively halted negotiations with the players’ union over the economic terms of the 2020 season — and that didn’t even constitute the worst news on a day that also saw the novel coronavirus pandemic assert its ultimate dominion over the entire endeavor.

While the afternoon hours Friday were consumed with the sobering news that five players and three staff members of the Philadelphia Phillies at the team’s spring training headquarters in Clearwater, Fla., had tested positive for the coronavirus — leading to the closing of the team’s facilities and an expansion of testing and contact tracing for other personnel on site — the evening brought a statement from the union that signaled the endgame had arrived for the bitter, months-long negotiation over the 2020 schedule.

What we’re left with: The last resort for MLB to salvage a 2020 season would be to impose a 50-game, late-summer mini-season and hope even that can be pulled off amid a worsening public-health crisis that already has shown up across big league organizations.

“MLB has informed the Association that it will not respond to our last proposal and will not play more than 60 games,” the union said in a statement Friday night. “Our Executive Board will convene in the near future to determine next steps. Importantly, Players remain committed to getting back to work as soon as possible.”

But the apparent finale of the economic negotiation — which found the sides stuck with a 10-game gap between the union’s last proposal for 70 games and MLB’s pitch for 60 — was not even the worst development for the sport’s hopes of taking the field in 2020.

Friday’s news out of Phillies camp, the first known outbreak for a major league team, may not have doomed the season, but it was enough of a setback to call into question the likelihood of finding a feasible path — with or without a deal on economics — through the pandemic.

It was also a sobering reminder of how difficult it will be for any team sport, baseball included, to pull off any sort of schedule this year. While MLB and the union haggle over the terms of the season and the money each side receives, the virus ultimately will decide how much — or whether — baseball will be played in 2020.

The extent of the Phillies’ outbreak, first reported by NBC Sports Philadelphia and later confirmed by the team, remains unknown. The eight positives came from a batch of 16 total tests, and another 32 employees, including 20 major and minor league players, were awaiting results. None of the affected personnel were identified. Additional testing had been done on families of those potentially infected, and contact tracing was underway.

By late Friday evening, USA Today and the Athletic had reported that MLB will temporarily close all spring training sites in Florida and Arizona for cleaning and will not allow players or staff members to return without first passing a coronavirus test.

“The Phillies are committed to the health and welfare of our players, coaches and staff as our highest priority,” Phillies managing partner John Middleton said in a statement, “and as a result of these confirmed cases, all facilities in Clearwater have been closed indefinitely … and will remain closed until medical authorities are confident that the virus is under control and our facilities are disinfected.”

The Toronto Blue Jays also reportedly shut down their spring training headquarters in Dunedin, Fla., about six miles from the Phillies’ facility, after a player exhibited coronavirus symptoms. According to ESPN, the Blue Jays player in question had recently spent time with players in the Phillies’ minor league system. In addition, the Houston Astros confirmed media reports that a player on their 40-man roster had tested positive. And the Washington Nationals recently had a minor league player in the Dominican Republic test positive for the coronavirus, according to a team spokesperson. Players and staff members at their academy there were tested because a family member tested positive, but results for those who had been at the facility were all negative.

Personnel from teams across the sport had been mobilizing in recent days, with the potential that an economic deal by the end of the weekend could result in camps opening next week — beginning with mandatory coronavirus tests for all personnel — either at spring training hubs in Arizona and Florida or in teams’ home cities. The mobilization was triggered in part by Commissioner Rob Manfred’s declaration June 10 that there “unequivocally” would be a 2020 baseball season — comments he backed off five days later.

But within an exchange of angry letters between MLB and union lawyers last weekend, as the tenor of the negotiations grew more strained and bitter, came the revelation that “several” big league players and staff members had tested positive. It was unclear whether any of those cases stemmed from the Phillies.

“The proliferation of COVID-19 outbreaks across the country over the last week, and the fact that we already know of several 40-man roster players and staff who have tested positive, has increased the risks associated with commencing spring training in the next few weeks,” MLB deputy commissioner Dan Halem wrote to the union Monday.

Notably, MLB has been focused on a plan for teams to play at their home stadiums wherever possible, with teams grouped geographically to cut down on travel. This stands in opposition to plans being pursued by the NBA, the WNBA and MLS to operate in protective, quarantined “bubbles” contained within one location.

With the battle over the division of money now apparently over — following months of acrimonious, back-and-forth posturing — MLB is left to decide whether it wants to impose a mini-season, leaving itself open to a potential $1 billion grievance the union would almost certainly file, or use the spread of the virus across the game’s ranks as a reason to punt on 2020 entirely.

At the same time, the players have the choice between accepting MLB’s latest proposal for a 60-game season — which would come with an expanded postseason and an agreement to waive potential grievances — or rejecting the proposal and accepting whatever imposed schedule, probably in the 50-game range, MLB comes up with.

MLB has remained adamant any plan for a 2020 regular season must conclude by the end of September, so that the postseason can be contained within October, due to fears a second wave of coronavirus in the fall could force the postseason’s cancellation and deprive the sport of lucrative television revenue.

Florida, the spring home of 15 major league teams and the regular season home of the Miami Marlins and Tampa Bay Rays, has seen its coronavirus numbers spike in recent days, with 3,822 new cases reported Friday — a one-day record for the state. On the same day news emerged of the Phillies’ outbreak, the NHL’s Tampa Bay Lightning shut down operations after three players and two staff members tested positive.

Arizona, California, Georgia and Texas also have seen spikes in coronavirus cases in recent days. Eleven teams, more than a third of the major league total, play in Arizona, California, Florida, Georgia and Texas.

At the same time, MLB and the union had yet to reach agreement on health and safety protocols, though both sides at various times have indicated an agreement was close. The basis of those talks was a 67-page proposal from MLB covering issues such as testing and social distancing and calling for anyone who tests positive to be quarantined away from the team.

However, there had yet to be a protocol established for dealing with a widespread outbreak. On Friday, the Phillies’ statement ended on an ominous note that made no guarantees regarding the 2020 season:

“In terms of the implications of the outbreak on the Phillies’ 2020 season,” the team said, “the club declines comment, believing it is too early to know.”

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