LJ Rader tries to be online as much as possible during big sporting events, but he missed the first half of last Sunday’s N.F.L. playoff game between the Buffalo Bills and the Kansas City Chiefs because of a dinner engagement. After he left the restaurant, Mr. Rader checked his phone and saw an unusual request: The N.F.L. had tagged him on X, formerly known as Twitter, hoping he would deliver one of his signature creations.

“I would’ve been so mad if I was still eating and had missed this,” Mr. Rader said.

On social media, Mr. Rader is the wizard behind Art But Make It Sports, where he uses accounts on X and Instagram to pair photographs from the world of sports with paintings and other pieces of art that mirror them. Witty, irreverent and often poignant, the accounts have a combined 365,000 followers.

Last Sunday, the N.F.L. wanted Mr. Rader’s take on a scene that was destined for internet immortality: Jason Kelce, an offensive lineman for the Philadelphia Eagles, was screaming, shirtless and clutching a can of beer as he leaned out of a stadium luxury box in subarctic weather to celebrate a touchdown that his brother, Travis, had scored for Kansas City.

Mr. Rader did his own brand of mental calculus as he sought the perfect piece of art to match the image: What was the most important element of the photograph?

“It’s the fact that he’s not wearing a shirt,” Mr. Rader said. “If I were to find a similar scene but the person has their clothes on, it’s not going to hit.”

And then it dawned on him: “The Feast of Bacchus,” by the 17th-century Dutch painter Philips Koninck, which depicts the Greek god of wine and revelry in a state of cherubic, half-naked bliss.

“Nailed it,” the N.F.L. wrote in response to the post, which has since garnered more than 95,000 likes on X.

Kathryn Riley, a photographer based in Boston who shot the image of Jason Kelce that Mr. Rader used, recalled the questions she asked herself when she saw the post: “How does this piece of art align so perfectly with the photo? And how did he know this piece of art even existed?”

The internet is a crowded place, but Mr. Rader, 34, has managed to do something novel. A largely self-taught art aficionado from the Upper East Side, Mr. Rader has summoned his gift for instant recall to highlight the artistry and absurdity of sports. In identifying those parallels, he has brought fine art to a new audience while showing the art world that beauty and emotion can surface in surprising places — on a soccer pitch, on an ice rink or on an N.B.A. bench.

Mr. Rader has matched a photo of an exhausted distance runner with a Baroque-period painting of Jesus Christ. He has amplified the excellence of Michael Jordan through the abstract brushstrokes of Clyfford Still. He has called on Salvador Dalí’s melting clocks to underscore a tennis player’s temper tantrum, likened a baseball player to a piece of taxidermy and linked athletes with sculptures by Rodin.

The pathos in those classic works of art is echoed by the sports moments that Mr. Rader chooses to highlight, and those comparisons only seem to elevate everyone involved — the artists, the photographers and, of course, the athletes. “There’s this sense that this thing from 300 or 400 years ago is happening again,” Mr. Rader said.

The main difference is that it is happening on a football field instead of inside a church.

“LJ brings art to the people,” said Bisa Butler, a contemporary artist whose work Mr. Rader has showcased. She added, “It has often been said that athletes’ movements are as graceful as dancers’, and LJ has gifted us his vision of athletic beauty and fine art.”

Sometimes it isn’t that serious. Consider Mr. Rader’s recent side-by-side comparison of Mike McCarthy, the coach of the Dallas Cowboys, and “Mound of Butter,” a late 19th-century still life by Antoine Vollon. Mr. Rader said he was not making fun of Mr. McCarthy’s size.

“It’s just the same outline of his face,” Mr. Rader said, adding that butter is “bland like his play calling and, most important, melts like him each year in the playoffs.”

Mr. Rader said his grandmother, Judith Best, imbued him with an appreciation for art when he was growing up in Katonah, N.Y. As a student at Vanderbilt, he took an art history course.

And while that was the extent of Mr. Rader’s formal education in the subject — he now works as a director of product at a sports data and technology company — he continues to frequent museums and has about 10,000 images of artwork on his phone. (One of his folders is labeled “Meme Fuel.”) He also has a Substack, where he shares exclusive content with subscribers.

But back when Mr. Rader started about four years ago, he was simply sticking captions on images of art. For example, when the Knicks fired David Fizdale as their coach in December 2019, Mr. Rader popped that news into a small caption at the bottom of “Salome With the Head of St. John the Baptist,” a 16th-century oil painting by Andrea Solario and one of the more elegant depictions of a decapitation.

Over time, Mr. Rader realized that instead of writing captions, he could simply pair the painting with a sports photo. One of the earliest iterations of that style was an emotive photo of the quarterback Philip Rivers, which Mr. Rader paired with “Study for the Nurse in the Film ‘Battleship Potemkin,’” by Francis Bacon. The painting is of a naked, screaming woman.

The response, Mr. Rader said, was “overwhelming.” He had stumbled upon internet magic.

Why does it work? Sports and art tend to be viewed as separate worlds, Mr. Rader said.

“But I think I’m showing that these two disciplines share a lot of similarities in terms of composition and emotion and talent,” he said, “and that maybe we’re not so different after all.”

Like any sharp-eyed social critic, Mr. Rader can also be unsparing. The Jets were in the first minutes of their season-opening game against the Bills in mid-September when the television broadcast caught Robert Saleh, the Jets’ coach, on the sideline “looking like he didn’t really want to be there,” Mr. Rader said. So he paired a screenshot of Mr. Saleh with “Self Portrait in Hell,” by Edvard Munch. The painting is over 100 years old. The Jets went on to finish with a losing record for the eighth straight season.

“I think the other theme that tends to come up a lot is that time is a flat circle,” Mr. Rader said.

He cited the early Renaissance Dutch painter Hieronymus Bosch as someone who might not seem super relatable. But Bosch’s work, which Mr. Rader has combed to make comparisons to college students tearing down a goal-post, the Denver Nuggets’ Nikola Jokic and a championship parade, conveys human emotions that are universal and enduring.

Angie Treasure, the senior director of content for the Utah Jazz, enlisted Mr. Rader last summer to collaborate on the team’s 2023-24 schedule release.

“He’s a savant,” Ms. Treasure said. “I remember everyone was shocked when they learned he wasn’t just putting photos through an A.I. generator.”

As Mr. Rader’s work has grown in popularity, speculation has spread among his followers — some more cynical than others — about how he goes about his business, including suggestions that he must be using artificial intelligence. Mr. Rader said that was absolutely not the case. First, he said, his work predates ChatGPT and other A.I. tools. Second, what would be the fun of using a computer?

“I do it for the enjoyment of it,” he said. “It keeps me sharp and gets me out of the house and gets me going to different galleries and shows and museums.”

In an interview over video chat, Mr. Rader asked to be presented with a batch of sports photos so that he could be tested on the spot.

Amid a series of uncanny comparisons, Mr. Rader needed about 2.7 seconds to match a photo of “The Catch,” Dwight Clark’s touchdown reception for the San Francisco 49ers in the 1981 N.F.C. Championship Game, to “The Intervention of the Sabine Women,” an 18th-century painting by Jacques-Louis David. In the painting, it is not the main subject that resonated with Mr. Rader, but rather a woman in the background who is holding a baby over her head as a battle engulfs her. (She could have been catching a football amid a swarm of defenders.)

Mr. Rader has a knack for recalling patterns and themes from artwork that he has seen and studied, he said. That skill set does not translate to other facets of his life.

“I’m always forgetting my keys,” he said.