ARLINGTON, Tex. — A tenuous, chaotic baseball season played amid a global pandemic was able to glide toward its finish line this week thanks in the large part to the sacrifices and adaptations of its participants. On Friday, the morning of Game 3 of the World Series, MLB announced no new positive tests for the novel coronavirus among its latest batch of tests. No players had tested positive in 54 days. By Monday, the day before Game 6, the streak was up to 57.

But the streak ended in shocking fashion at Globe Life Field on Tuesday night — sullying the otherwise electrifying and compelling story of the Los Angeles Dodgers’ victory over the Tampa Bay Rays for the franchise’s first championship since 1988 and leaving behind pointed questions about Justin Turner’s actions and the repercussions thereof.

By returning to the field in the aftermath of the clinching win Tuesday — after leaving in the eighth inning following the news of a positive test and being placed under isolation, per MLB’s protocols — Turner and the members of the Dodgers who backed him thrust baseball directly into the larger societal divide over how to deal with a virus that has killed more than 226,000 Americans.

On Wednesday afternoon, MLB said it was investigating the matter with the players’ union “within the parameters of their joint 2020 operations manual.”

“Following the Dodgers’ victory, it is clear that Turner chose to disregard the agreed-upon joint protocols and the instructions he was given regarding the safety and protection of others,” MLB said in a statement. “While a desire to celebrate is understandable, Turner’s decision to leave isolation and enter the field was wrong and put everyone he came in contact with at risk. When MLB Security raised the matter of being on the field with Turner, he emphatically refused to comply.”

In its statement, MLB added that everyone in L.A.’s traveling party was given nasal swab tests. Both the Dodgers and Rays were tested again Wednesday before traveling home, though a person familiar with the matter said there were a few exceptions with the Dodgers. USA Today reported that Turner and his wife did not fly with the team back to Los Angeles.

MLB was mere hours away from a satisfying conclusion to a fraught season when Turner was pulled. According to a timeline provided by a person with knowledge of the matter, Turner’s test from Monday — personnel within the quarantined postseason bubble were tested daily — came back as inconclusive in the second inning Tuesday, prompting MLB to ask for an expedited analysis of his Tuesday sample. Baseball officials were informed around the sixth inning that Turner tested positive.

Once the news was relayed to the Dodgers’ dugout, Manager Dave Roberts pulled Turner — the oldest and longest-tenured Dodgers position player and a popular figure often called the heart and soul of their clubhouse — before the start of the eighth inning, and Turner was placed in isolation. As such, he missed the final out of the Dodgers’ clincher, the joyous scrum of players on the infield and the first part of the on-field celebration.

It was an absence that angered some of his teammates, with shortstop Corey Seager, the World Series MVP, saying: “To take that away from him is gut-wrenching. I can’t imagine how he feels. That guy more than anybody deserves to take his picture with that trophy and celebrate with us. That got taken away from him. That doesn’t sit right with me.”

But only minutes later, Turner had returned to the field, initially wearing a mask. He hugged teammates, staff members and the wives and girlfriends of teammates. He posed near the World Series trophy for a team picture, slipping his mask below his nose and mouth and later taking it off completely. Directly next to him was Roberts, who was diagnosed with a form of cancer in 2010.

Dodgers President of Baseball Operations Andrew Friedman justified Turner’s actions, saying: “We can’t state strongly enough how big a role he played for this organization. I don’t think there was anyone that was going to stop him from going out.”

As it turned out, MLB security and other MLB officials did attempt to keep Turner isolated, but Turner refused. It is unclear how far the actions of the security personnel went — or whether they even had authority to detain Turner. According to a person with knowledge of the situation, MLB was acting as if the 2020 safety protocols were still in place. The official end of the season, a strikeout by Dodgers lefty Julio Urías, did not change how it tried to handle the situation with Turner, the person said.

MLB’s updated protocols, agreed upon by owners and the players’ union, stated that “after a Club receives notice of a positive test result for a player or staff member, the Club notifies the infected individual [and] requires him or her to isolate (meaning no contact with anyone other than medical professionals) until they are cleared to return to Club facilities.” By that wording, if the protocol was enforced and Turner not appeased, he should have been isolated and not around coaches, teammates and so on.

It is also true, as Friedman pointed out, that Dodgers personnel who were in contact with Turner on the field probably had already been exposed to him, given the nature of the bubble and the proximity in the dugout and other areas.

“From a contact tracing standpoint,” Friedman said, “we all are kind of in that web.”

However, Turner, clearly, also made close contact with people — family members of players — with whom he may not have previously interacted and who may not have even been aware of Turner’s positive test. At one point Turner removed his mask again to pose on the mound with the trophy, alongside his wife, Kourtney, leaning over to kiss her. Afterward, she quickly raised her mask.

Among the questions yet to be answered in the messy aftermath of Game 6 was how Turner contracted the virus in the supposedly quarantined environment of the MLB postseason bubble — he released a statement on social media only saying he was asymptomatic — and what would have happened had the Rays come back in Tuesday night’s late innings and forced a Game 7. During the regular season, a single positive test among the Cincinnati Reds prompted a three-day shutdown of that team. A person with knowledge of MLB’s thinking said officials would have consulted medical advisers, as they did all season, and a postponement would have been in play. MLB postponed 45 games during the regular season to allow additional time for contact tracing and follow-up tests.

There was some irony in the fact it was Turner and the Dodgers at the center of baseball’s coronavirus controversy. The Dodgers were both baseball’s best team throughout the 2020 season and arguably its most vigilant when it came to staying safe — two facts that may not have been mutually exclusive. They were one of only nine teams to have no players test positive during the 60-game regular season.

On July 31 — in the midst of twin outbreaks on the Miami Marlins and St. Louis Cardinals that had placed the rest of the season in jeopardy and the same day Commissioner Rob Manfred telephoned union chief Tony Clark asking for help in getting players to do a better job of adhering to the protocols — Turner texted a reporter for the Dodgers’ television rightsholder with a list of enhanced protocols the players had adopted on their own.

Among them: mandatory mask-wearing in the dugout and bans on pitching coaches from being in the dugout while the team was batting and hitting coaches in the dugout when the team was on defense. Five days later, MLB sent a memo to teams mandating its own enhanced protocols, some of which were the same as what the Dodgers’ players had enacted on their own.

By the time baseball reached the postseason, eventually launching separate bubbles in Southern California and Texas, MLB officials, team officials and players may have thought they were safe from further outbreaks. Personnel were not permitted contact with anyone outside the bubble. The Dodgers were ensconced in a hotel about 20 minutes from Globe Life Field.

“There was a point during the shutdown [of March-July] that I was on a lot of those phone calls and I wasn’t sure if we’d get to the point of having a season,” Turner, the Dodgers’ union player representative, said this month. “With all the stuff going on in the world right now, I’m proud of the players and staff. All the work that’s gone into the protocols and making good decisions and the right choices to make sure we were able to have a season.”

Pulling off the postseason under these circumstances required personal sacrifices even beyond those of the regular season. Some players whose wives and children chose not to enter the MLB bubble had gone weeks without hugging or even touching them.

“Seeing my family, not even close,” Rays pitcher Charlie Morton said when asked what he looked forward to most about leaving the bubble. His family decided to remain at home in Florida because of school, and when they came to Globe Life Field for his start in Game 3, he could only wave to them from the field. “Just being there for my wife and kids. And just being able to sit down at breakfast or dinner together. That’s everything to me. That’s the most important thing by far.”

Rays shortstop Willy Adames likewise could only wave to his family in the stands. “I’m like, ‘I can’t even give you a hug, and you’re like 30 feet [away]’. … It’s hard, but you have to make a sacrifice in the situation we’re in now,” he said.

Given the experiences of the Marlins and Cardinals, for whom one positive case turned into several and then dozens, the fear now is that the World Series could become a superspreader event. That may not be known for days, given the virus’s incubation period.

But what is clear is that, at least for Turner and the Dodgers, a season of difficult sacrifices — in which they were industry leaders — ended late Tuesday night with the final out of the World Series.