It has been 16 weeks since there was baseball, since expanses of green were last filled with the thwacks of baseballs colliding with wooden bats and leather mitts, since there were injury reports and roster battles to consider and performances to parse. The intervening days, for both the sport and the country, have been filled with tumult, upheaval and a gnawing sense of unsettledness. The coming days, for that matter, might, too.

But beginning Friday, baseball — or something very much resembling it — is back. Its return comes in such a twisted, ahistoric form, it required a new name for the workouts that start this weekend at Nationals Park and 29 other home stadiums — with Major League Baseball choosing “summer camp” over such contenders as “spring training 2.0” or “second spring.”

It will be unlike anything the sport has ever seen, but if this three-week experiment is successful — which is to say, if the sport gets through it without infecting large swaths of its personnel with the novel coronavirus still spreading rapidly in parts of the country — it will lead to an Opening Day on July 23 or 24, nearly four months behind schedule, and a breakneck, 60-game season that would be by far the shortest in baseball’s modern history.

For players, the reopening of camps, which were shut down across Arizona and Florida on March 12 for what MLB hoped at the time would be only a month or so, will provide sobering reminders from the outset — and at almost every turn — of how much the world has changed since then.

When players enter their own home stadiums — which have been calibrated and demarcated to promote social distancing — they will be expected to wear masks. There will be multiple temperature checks daily, coronavirus testing every other day and antibody tests via blood samples every few weeks.

There will be additional social distancing protocols — workouts conducted in limited numbers and staggered by time, empty lockers in between occupied ones, groups of players shifted from the home clubhouse to the visitors’. No spitting, hugging or high-fives.

“We have to accept to a certain degree that we are not truly in control,” Colorado Rockies General Manager Jeff Bridich said. “It’s going to be easy to fall back into our normal rhythms and habits as we get back into practicing and playing games. But this isn’t business as usual.”

Not everyone will be there. Dozens of players, including several members of the Philadelphia Phillies, have tested positive for the coronavirus, with the sport bracing for dozens more when the aggregate results of intake testing are released as soon as Friday.

In addition, at least four players on big league rosters — Joe Ross and Ryan Zimmerman of the Washington Nationals, Ian Desmond of the Rockies and Mike Leake of the Arizona Diamondbacks — chose not to play, forgoing their salaries in the process. At least three coaches, all of them 60 or older, were asked by their teams to stay home and contribute remotely.

Those who remain will be asked, though not mandated, to limit their interactions away from the field to only immediate family members, a message that is expected to be hammered home over the coming days as players begin workouts and managers contemplate their speeches to the group. Perhaps never before in baseball history has the self-policing of each clubhouse been so crucial.

“There’s going to be things that are a nuisance, probably, on a daily basis that you’re going to have to navigate and get through,” New York Yankees Manager Aaron Boone told reporters. “I believe one of my biggest jobs is to make sure that there’s a message that guys are constantly enforcing with one another and that we’re constantly holding each other accountable.”

Roster construction, a crucial undertaking of any spring training, is doubly so in summer camp, with rosters expanding to 30 players at the start of the season, the designated hitter coming to the National League, starting pitchers unlikely to be prepared for lengthy starts from the outset and a new extra-innings rule (each inning will begin with a runner on second base) that could place added value on the ability to lay down a bunt or serve as a pinch runner.

Not everyone, inside or outside the sport, is a fan of all the 2020 rule changes, but clearly — and understandably, given the circumstances — the sport chose expediency over aesthetics and experimentation over rigid adherence to tradition.

With the rule changes, the 60-game schedule and the lack of fans in the stands, at least initially, there have been questions over the legitimacy of whatever outcome the season produces. But this year’s World Series champion — should the virus allow baseball to get that far — won’t consider its title any less meaningful than any other and perhaps even more so.

“Playing 162 games in a typical season, that’s one of the great challenges of what we do,” Cincinnati Reds Manager David Bell told reporters. “There’s no denying that this is a completely different season, but I would say that, actually, [the 2020 World Series champion will be] a team that overcame the greatest challenges any of us have ever been a part of.”

It is difficult to remember now, but back in the second week of March, before the world turned upside down, baseball was still largely obsessed with how the Houston Astros — whose sign-stealing scandal dominated the offseason and much of the spring — would be treated in visiting parks across the league. (Now, with no fans in stadiums, the only question is whether opposing pitchers still care enough to buzz them with fastballs.)

The other big stories were the nagging elbow injury of Boston Red Sox ace Chris Sale, who ultimately required ligament-replacement surgery a week after the shutdown, and the nine-year, $215 million contract extension signed by Milwaukee Brewers superstar Christian Yelich. The Phillies and Oakland A’s were leading the standings in the Grapefruit and Cactus leagues, respectively.

The number of confirmed coronavirus cases across the United States had just surpassed 1,000. This week, the number climbed to more than 2.7 million, with some 50,000 new cases reported each day.

Back then, Yankees standouts Aaron Judge, Giancarlo Stanton, Aaron Hicks and James Paxton were all shelved with injuries. Now they might all be ready for Opening Day in three weeks.

“We have 60 games to go out and prove our worth,” Boone said.

Nearly four months after it went away, baseball is back. At a time when teams should be just past the midway point in their 162-game seasons, with the All-Star Game at Dodger Stadium (now canceled) looming less than two weeks away, the sport is just getting started.

It may look almost nothing like it did when it went away, and the whole enterprise may not make it to August, let alone October. But for as long as it lasts, this baseball season, in all its daily madness, will be something to behold.

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