Last week, on what was meant to be Opening Day at Fenway Park, Josh Kantor leaned over the organ in his living room and kicked into a textbook rendition of “Take Me Out to the Ball Game.” Then he looked up at his iPhone, which was broadcasting live to the Facebook masses.

“I’m really missing Fenway today,” said Kantor, wearing a tie over his Red Sox shirt for the special occasion. “But instead we’re here, we’re doing this, and I will miss Fenway a lot less because I will be here with all of you.”

Normally, Kantor is in a perch at Boston’s venerable baseball park, churning out tunes as the home team’s official organist. In late March, with the season put on pause because of coronavirus concerns, he decided he would try a single video stream from behind his Yamaha Electone and leave it at that. But the online response persuaded him to come back the next day. And the next. Kantor is now pledging to continue the “7th-Inning Stretch,” as he calls his 30-minute show, until baseball returns or people get sick of it.

The “Stretch” airs daily at 3 p.m. as Kantor, aided by his wife, Mary Eaton, takes requests, offers music-and-baseball-related anecdotes and taps into a reservoir of songs that range from Motown and polkas to the Clash and the Replacements.

Regular listeners include R.E.M. manager Bertis Downs, ex-Pogues bassist Cáit O’Riordan and some of his Major League Baseball organ-playing peers. There’s also his mom, college pals and Matt Pelletier, a 41-year-old insurance claims handler from East Longmeadow, Mass., who has never met Kantor but is extremely grateful he’s there.

“It’s therapy,” says Pelletier. “If we can’t be in Fenway Park watching them play, at least I can hear him play, and it just brings back a little bit of normalcy.”

With his thick beard, sideman persona and seemingly unlimited musical vocabulary, Kantor, 47, has been compared to The Band’s keyboard whiz, Garth Hudson. But in his newfound hosting role, Kantor has found his voice and a soft-spoken sense of humor that includes a benevolent brand of music snobbery. He’ll tell you he doesn’t care much for Journey but still churns out “Separate Ways,” and will deliver “How Sweet It Is (to Be Loved By You)” only after reminding you that the Marvin Gaye original is far superior to James Taylor’s cover.

And if Kantor’s daily ritual is meant to maintain some normalcy, Kantor’s skills are anything but routine. In recent days, he’s organified “Stairway to Heaven” and re-created Mark Knopfler’s lightning-fast guitar solo on “Sultans of Swing.” Bobby Cressey, organist for the San Diego Padres, watched as Kantor, on camera, worked through requests for songs he’d never played before.

“Josh will pull it up on his phone, listen and be able to play it 30 seconds later,” he said. “I was blown away.”

That skill transcends the ballpark booth. Kantor is the only team organist who gets called onstage with Wilco and tours with members of Blondie, the Young Fresh Fellows and R.E.M.

Wilco’s Jeff Tweedy, who happens to be a St. Louis Cardinals fan, says that Kantor is known for his rare gift, the ability to basically play any song by ear.

“It’s freakish, to be honest,” Tweedy says. “Like a tape recorder. I’ve had him come up onstage with us at different times. ‘Do you know this song?’ He’s like, ‘Can you play it for me?’ And I’d play it for him for like 20 seconds, and then he comes onstage and nails it.”

“There’s a word that people used to use,” says Blondie drummer Clem Burke, whose side project, the Split Squad, includes Kantor. “Elephant ears. He can pick up music right away.”

That same approach governs him at Fenway, where he’s been the organist since 2003. Kantor, who began playing piano at 5, says he’s always been able to pick up songs quickly, even before he was trained. For his first few years with the Red Sox, Kantor worked off his own playlist. But in 2011, he began to take requests on Twitter. That led to the tightrope act Red Sox fans witness during games: They pitch song requests, and Kantor plays as many as he can.

“The first year, I’d get one or two a night,” says Kantor. “I now get about 15 a night. I tell people it has made the job twice as much fun and five times harder. So that’s not an awesome ratio, but it’s still worth doing, because twice as much fun is still twice as much fun.”

The Twitter request line has brought him fans who admit they don’t know the difference between a sacrifice bunt and a ground-rule double. O’Riordan saw her first-ever baseball game at Fenway, sitting in the bleachers in 1986 before a gig across the street. But she met Kantor in New York two years ago, when the Split Squad played a gig there. She started following him on Twitter and would notice a stream of requests on her timeline along with Kantor’s replies.

“ ‘Can’t Hardly Wait’ by the Replacements. You got it. Neutral Milk Hotel? Sure.” O’Riordan says. “What’s happening here? And eventually it sunk in. He’s amazing. You can throw anything at him.”

The “7th-Inning Stretch” arrived soon after Massachusetts residents were advised by Gov. Charlie Baker to stay at home. Kantor and Eaton, an ordained minister whose congregation is Boston’s homeless community, wanted to do something musical for the kids on their street in Cambridge. A friend emailed with a different idea: Why not go online and mark the start of the baseball season?

Though they had no experience with streaming, Kantor and Eaton set up a laptop in their living room, placed a 1981 Fleer card of former Red Sox slugger Jim Rice next to his bobbleheads of former Sox catcher Carlton “Pudge” Fisk and retired Chicago White Sox organist Nancy Faust — she remains one of his heroes, along with Stevie Wonder — and took his spot at the organ. As the show has developed, they upgraded to an iPhone, helping the sound and video quality. Last week, with the audience growing — there were more than 1,400 views for Sunday’s show — Kantor migrated from his personal Facebook page to the newly founded “7th-Inning Stretch.”

“This is a long haul,” says Eaton, known as “Rev. Mary” on the show. “It’s not that we’re bored. It’s that people are working really hard to figure out what to do and are exhausted mentally, physically and spiritually and need to stretch, just to give themselves permission to rest in the middle of the day. To have a respite. We need it.”

That’s been the case for the couple, as well. Because of Eaton’s work — she’s continuing to work with the homeless during the outbreak — the two sleep in separate rooms. During broadcasts, Kantor makes a pitch for donations to FeedingAmerica.org.

(Kantor, who also works part-time at Harvard’s music library, expects this week to start receiving a reduced paycheck, like all Red Sox seasonal employees.)

He has also not ignored the sadness of the moment, while finding a way to offer uplifting musical tributes. On consecutive days, Kantor opened with songs by Bill Withers, who died of heart issues, and Fountains of Wayne’s Adam Schlesinger, who died after contracting the coronavirus.

“Heartbreaking first pitch,” wrote one follower as he played “That Thing You Do!,” Schlesinger’s Beatles-esque song from the 1996 Tom Hanks film of the same name.

For O’Riordan, the former Pogues bassist, Kantor’s “Stretch” has become a new tradition. She’s usually not good at doing the same thing at the same time every day. This is different. She was in the shower and heard the discofied “Spinners” version of “Working My Way Back to You.” Kantor had taken her request that day and churned it out. Her only fear, as Kantor’s feed becomes more popular, is that it’ll be harder for her to get requests in.

“People need this,” she said. “What Josh is doing is vital, psychological medicine for people’s spirits.”