(Gastón Mendieta for The Washington Post)

As fields, arenas and stadiums sit vacant and silent, the desire for sports to return far exceeds the capacity among those who oversee them to determine when they will. Assessing probability is futile, but public health leaders indicate that fans and leagues should prepare for sports to remain absent not just for the coming months but into next year.

The novel coronavirus pandemic already has canceled or postponed the NCAA tournament, the Olympics and Wimbledon. It has jeopardized the NBA playoffs, the Stanley Cup playoffs, the Masters and the baseball and soccer seasons. It is possible the rest of the 2020 sports calendar, including college football and the NFL, also will be lost, according to interviews with and public comments from more than a dozen sports leaders and public health experts. Most stressed the uncertainty in such a fluid situation.

“From my point of view based on data — and I’m huge sports fan, so this is really hard — I can’t really predict or truly speculate,” said Jared Evans, a senior researcher at Johns Hopkins University’s Applied Physics Laboratory. “We need as a population to be prepared for anything. And also be prepared for that disappointment.”

Sports bodies at the professional and collegiate levels have planned for a range of contingencies that include playing in empty stadiums and canceling seasons altogether, and they are bracing for the impact of the worst of them. They are driven by both business and altruistic motivations, eager to salvage financial losses and to provide diversion to the public.

Athletes who have trained for the 2020 Olympics in Japan are focusing on what's ahead after the coronavirus pandemic forced the Games to be postponed. (Video: Jorge Ribas/The Washington Post)

President Trump held a conference call Saturday with 13 commissioners and leaders from major American sports. At a news conference later in the day, he reiterated his desire to “open our country” and said sports leagues want to return soon.

“I want fans back in the arenas,” Trump said. “By whenever we’re ready, as soon as we can. And the fans want to be back, too.”

Asked specifically about opening stadiums and arenas to fans by August, Trump said he could not commit to a date.

“But I think it’s going to be sooner rather than later,” he said. “We’re not going to have separation for the rest of our times on the planet.”

Earlier Saturday, reporters asked California Gov. Gavin Newsom (D) at a news conference whether he expected major sporting events with fans in stadiums by August or September. “I’m not anticipating that happening in this state,” he replied.

Disease experts suggest that the possibility feared most in the sports world — no major events for the rest of the year — may be more real than many believe and that putting a timeline on their return is not yet feasible.

“My crystal ball is not just cloudy,” Ali Khan, dean of the University of Nebraska Medical Center’s College of Public Health and former director of the Centers for Disease Control and Prevention’s Office of Public Health Preparedness and Response, said this week. “It’s black.”

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When Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases and part of the White House’s coronavirus task force, was asked this week about people looking forward to baseball games and concerts this summer, he did not answer directly. He said the only way to stop the virus is a vaccine, which experts expect will not be ready before early 2021.

“Unfortunately, I think perhaps if anything, having large spectator sports open back up may even have to be delayed a little bit longer than relaxing some of the other things,” said Dean Winslow, an infectious-disease doctor at Stanford. “I hate to say that because I’m a big sports fan.

“There’s also the scenario a lot of people worry about, including my friend Dr. Fauci, that if you relax the control measures too soon, you could potentially induce a second wave of transmission to susceptible people,” Winslow added when asked about professional and college football starting on time. “It’s a little too soon to make that prediction. I certainly don’t think it’s impossible that we’ll be able to start resuming things such as sporting events by the early fall.”

The yearning among fans for sports’ reappearance collides with reality. The U.S. Tennis Association said this week that it still plans to stage the U.S. Open as scheduled from late August through mid-September in New York. The site of the tournament, Billie Jean King National Tennis Center in Flushing Meadows, is being converted to a temporary hospital.

The leaders of the NFL, after its medical director addressed team owners Tuesday, expressed confidence its season would begin as scheduled, without conditions. But days earlier, ESPN college football analyst Kirk Herbstreit, a bellwether for the sport, said in a radio interview that he would be “shocked” if any NFL or college football was played this fall.

Pac-12 Commissioner Larry Scott told the Mercury News this week that the conference has reviewed multiple models for how the college football season could unfold. In the most optimistic, training camp will be standard and the season will start on time.

“The most pessimistic,” Scott said, “has no season at all.”

When to say when

How will we know it is safe for sports again? It is a thorny question, as other parts of the world have discovered.

In China, as coronavirus cases started to drop and everyday life appeared to stabilize, the Chinese Basketball Association targeted an April 15 return. Government restrictions pushed the date back to early May. This week, as cases started to rise again, the league announced an indefinite pause.

Nippon Professional Baseball, Japan’s top league, could serve as a cautionary tale for Major League Baseball. With the number of new cases on the way down, NPB officials began preparing for a delayed start to the 2020 season, pushing its scheduled Opening Day from March 20 to April 24. Teams began playing exhibition games in empty stadiums.

However, on March 26, three Hanshin Tigers, including star pitcher Shintaro Fujinami, tested positive for the coronavirus, according to the Associated Press. The team responded by canceling its scheduled exhibition games, ordering players and staff to self-quarantine for 14 days and disinfecting its home stadium.

NPB still planned to open the regular season April 24, but as Japan’s coronavirus outbreak worsened, that became untenable. On Friday, league officials announced an indefinite extension to its delayed start.

U.S. experts said opening stadiums in this country would be among the last stages of lifting pandemic-related restrictions. The first step would be letting people go back to work, with social distancing still in place. Travel restrictions would thaw. Only after those changes could authorities consider allowing stadiums to open.

The best-case scenario, Winslow said, is that social distancing and other restrictive measures combined with higher temperatures lead to a dramatic decrease in cases by late May.

“That would potentially give public-health people the incentive to at least consider starting to relax these restrictions,” Winslow said. “That would mean allowing potentially sporting events and concerts and that sort of thing to happen by the early fall.”

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Even if the seasonal change provides relief, it may be temporary. The 1918 flu pandemic diminished over the summer, then returned in the fall and lasted into 1919.

“The public health and epidemiologists are saying, ‘The biggest tragedy we could have would be if we think we’ve got a handle on this and we’re still going to have whatever the projection is — it may be 100,000 deaths — and we allow people to go back to normal everyday life and then infections happen again,’ ” Evans said. “That kind of slow rollout back to normalcy is going to be something that’s difficult for everyone.”

Allen Sills, the NFL’s chief medical officer, addressed owners on a conference call Tuesday, and league leaders said afterward they were focused on playing an uninterrupted 2020 season.

“We’re looking at a full season,” NFL general counsel Jeff Pash said. “We did not discuss in either of our calls [with team presidents and owners] issues of a shortened season or any changes in the structure of the season. We’re planning on going forward with a regular, complete season.”

The NFL later softened its public stance, with Sills telling NFL.com on Thursday that “everyone’s hope” is a full season but it may not be feasible.

“The reality is none of us know those facts for certain right now,” Sills said.

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Despite the outward confidence, several franchises have pushed back deadlines for season ticket buyers to make payments and reminded them of policies on canceled games. One high-ranking NFC team executive, who spoke on the condition of anonymity to discuss the matter frankly, said the NFL should be prepared for any possibility. “The biggest mistake you can make right now,” he said, “would be to make an assumption.”

The NFL has an easier path to return than college football. It would be unlikely and maybe impossible to start the season if students are not allowed on campus; Ohio State is one of several schools that have declared all summer classes will be taken online. The NFL has an option to try to separate players from the broader public that college football does not.

“I can’t see us playing football without students, because athletes are students,” West Virginia University President E. Gordon Gee said. “I can’t see us playing football without fans in the stands and without students out there to support our team.”

The possibility of a canceled NBA postseason, coupled with lost sponsorship from China after a preseason ordeal, could push the NBA’s total revenue loss over $1 billion. The scope of the financial damage prompted Commissioner Adam Silver and other NBA executives to take 20 percent pay cuts. The NBA has made it clear that it is considering all manners of rescheduling, including delays that could push the 2019-20 season into the late summer or early fall and require, in turn, that the start of the 2020-21 season be delayed until Christmas.

The NBA has explored multiple scenarios for salvaging the postseason, most geared toward preserving a product for its television partners. Decision-makers understand that playing games in front of thousands of fans this summer is unlikely and that the league might need to switch to a single-site destination, such as Las Vegas, to host a quarantine-friendly tournament.

Quiet but safe?

In early March, MLB officials considered the option of playing games without fans to be a last resort. But in recent days, with the regular season on indefinite delay and concerns becoming more urgent, baseball officials have softened their stance toward the notion of playing games without fans.

“Very open,” MLB Players Association chief Tony Clark said when asked about the possibility of playing in empty stadiums. “That possibility exists. … The players are open to having a discussion about just about everything. Right now, no door is closed.”

Playing games without fans is safer. But is it safe? Winslow said once travel restrictions ease and transmission is proved to be down, it would be. “I don’t think that’s beyond the realm of possibility at all, that we might be able to do that safely a few months from now,” Winslow said.

First, the number of players and support staff required to stage a game would have to be less than any public-gathering restrictions. As college basketball tournaments were canceled this March, many conferences first banned spectators, then canceled games before ever employing that strategy.

“You want to be confident all the individuals that are participating have either no virus and a very low chance,” Evans said. “This doesn’t make it a short time frame. I’m not saying it’s going to be years. I’m just saying there are going to have to be considerations in place as far as making sure the participants are tested. You have to have an understanding where they were, who they were in contact with.”

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The idea of creating a closed system for self-isolating players may be easier said than done. In a best-case scenario in which the NFL convenes for training camp early enough to start its season on time, what happens if one player tests positive for the coronavirus? In the NBA, one positive test caused the shutdown of the league. Could the NFL justify continuing its season? And could roughly 1,700 football players — plus an army of coaches, scouts and administrative staff — avoid infection?

“I don’t know how you let these guys go into locker rooms and let stadiums be filled up and how you can play ball,” Herbstreit said in an ESPN Radio interview. “... Next thing you know, you got a locker room full of guys that are sick. And that’s on your watch? I wouldn’t want to have that.”

For now, all leagues can do is wait. Sports can return only once the rest of society stabilizes, and that can happen only if social distancing guidelines are followed. It leaves sports fans in an unusual position: Rarely can they help their favorite teams win; now they might be able to help them play.

“If you want to have football and college athletics in the fall, take care of yourself now,” Gee said. “That’s probably as good of a message as I can put out right now.”

Dave Sheinin, Ben Golliver, Liz Clarke, Mark Maske and Samantha Pell contributed to this report.

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