BOSTON — The soundtrack of a baseball clubhouse tends to follow a predictable pattern, its beat sticking mostly with hip-hop, country, rock and Latin music. But when video clips emerged in recent weeks of the Boston Red Sox celebrating various playoff milestones, what stood out was the players’ enthusiasm — and full-throated singalong — to a melancholic club song from a Swedish pop star.

Or, more accurately, a Dutch DJ’s remix of a British singer’s cover of the Swedish pop star’s melancholic club song.

The Swedish star, Robyn, first wrote and performed the hit, “Dancing on My Own,” in April 2010. That was years before Calum Scott sang it for his audition on the reality show, “Britain’s Got Talent,” in 2015. The Dutch DJ, Tiësto, then added his own beats for the version adopted by the Sox.

How “Dancing on My Own” became the team anthem of the Red Sox’ 2021 season — which now includes a meeting with the Houston Astros in the American League Championship Series — is largely a story of catcher Kevin Plawecki’s enthusiasm for his speaker’s repeat button, but the tale has its roots in baseball’s 2020 pandemic restart.

When the Red Sox reconvened in July 2020 for the postponed start of the season, many players were away from their families. Four opted to live together: Plawecki and three now former teammates, Andrew Benintendi, Mitch Moreland and Kevin Pillar. Benintendi introduced the song to Plawecki, who immediately loved it and started playing it nonstop in the house, much to the apparent chagrin of Moreland.

“Moreland hated it — a ‘he said he hated it but really loved it’ type of deal,” Plawecki said. As a joke before an intrasquad scrimmage, the catcher decided, “I’m going to make it my walk-up song for Mitch,” who was playing first base for the opposing team. Plawecki homered in his first at-bat and sang the song to Moreland as he rounded the bases. At that point, Plawecki was hooked.

“The beat of it, the flow of it, puts you in a good mood,” said Plawecki, who called himself more a “vibe guy” while acknowledging that the lyrics — about a clubgoer watching a former lover with a new flame — “don’t make sense at all” for baseball.

In previous seasons, Plawecki had let his wife and brother choose his walk-up songs, but that home run convinced him to keep “Dancing on My Own” as his accompaniment for trips to the plate. At first, it was a way to have fun in an eerie season with no fans in the ballpark, but then Plawecki had the best offensive season of his career. While backing up Christian Vazquez over the truncated 60-game schedule, Plawecki batted .341 in 82 at-bats.

Since Plawecki, 30, carries his speaker with him everywhere, “Dancing on My Own” is now featured regularly before and after games.

“We play it all the time — just, too much,” Plawecki said, using a royal “we” and adding a profane descriptor to emphasize the growing volume of the play count. “We just overdo it.”

When infielder Christian Arroyo joined the Red Sox for the final stretch of the 2020 season, he was assigned the same luxury suite as Plawecki to use as a makeshift changing room because of Covid protocols. Arroyo grew to like the song even if, he estimated, Plawecki played it 75 times in two weeks. Arroyo eventually asked his teammate, “Kev, are you kind of overplaying it?” Plawecki replied, “No, this song is amazing.”

It has become a running gag this season — a Red Soxian Rickroll — where Plawecki will ask his teammates, “Hey boys, have you heard this new song?”

“And then we’ll fire it up, and everyone goes nuts,” Arroyo said during Wednesday’s workout as, no joke, “Dancing on My Own” played over the Fenway Park speakers and infielder Jose Iglesias raised his bat and danced to it near the batting cage.

“Now it’s become a little bit of a joke, but deep down, everybody thinks it’s a little catchy,” infielder Travis Shaw said.

“Ever since Kevin started playing that song in the clubhouse, on the bus, everywhere, that became our theme song,” reliever Hirokazu Sawamura said through his interpreter. “That’s part of who we are now.”

After the Red Sox beat the Tampa Bay Rays to close out their A.L. division series on Monday night, a portion of their frenzied, suds-soaked harmonizing of “Dancing on My Own” was broadcast on MLB Network and spread across social media. Robyn tweeted that the scene was “bonkers” and, when a fan asked if Calum Scott and Tiësto might perform it if the Red Sox win the World Series, Scott wrote, “In a HEARTBEAT.” (As of Thursday, Tiësto had not weighed in on his availability.)

Even though the song is such a critically-acclaimed hit that it ranks No. 20 on Rolling Stone’s 2021 edition of the 500 Greatest Songs of All Time, “Dancing on My Own” is the most unexpected update to the Red Sox’ 21st century sonic catalog, which includes mainstays like Neil Diamond’s “Sweet Caroline,” which Fenway Park has played in the middle of the eighth inning, and The Standells’ “Dirty Water,” which is played after every win.

There have been season-specific songs, too. The 2004 team adopted Enimen’s “Lose Yourself” during its World Series title run; the Dropkick Murphys wrote “Tessie” that same season and then performed “Shipping up to Boston” for the 2007 title team. In 2013, outfielder Shane Victorino’s walk-up song, Bob Marley’s “Three Little Birds,” always prompted the crowd to keep singing after the music stopped.

To be sure, Plawecki is not just a one-hit wonder — he is also credited as the primary inventor of the team’s dugout ritual of pushing a hitter who has homered in a laundry cart through a receiving line of high-fives — even if his music selection is still limited.

“I’m proud of him because, when the season started, he had a playlist of about five songs,” center fielder Kiké Hernandez said. “It was painful because it was just the same five songs over and over and over again. We started giving him a hard time, and he started coming with more songs.”

As the Red Sox took a bus from Baltimore to Washington between their last two series of the season, the veterans asked the rookies to stand up front and sing karaoke. The breakout star was Sawamura, who belted out a capable cover of Alicia Keys’s “If I Ain’t Got You.” Sawamura’s English may be limited but, according to Hernandez, “he knows every word to a few of Alicia Keys’s songs; Sawamura has a talent that not a lot of people have discovered yet.”

Sawamura said he has been a fan of English-language music for years, spanning Oasis and Keys to Ed Sheeran. “I have a large collection I can sing,” he noted. (Asked to review his bus-ride performance, Sawamura laughed and said, “I think I had the most excitement from the fans on the bus. I nailed it.”)

But when all the rookies had taken their turn, Plawecki walked up front and cued up “Dancing on My Own.”

“I sang it on the mic for all the boys in the back,” he said.