Brian Evans insists he’s never been a get-the-last-laugh kind of guy.

“No anger in me, no sir,” he says solemnly. But just before the first inning of a recent Red Sox home game — against the New York Yankees, no less — the in your face! ear-to-ear grin was unmistakable, as Evans, in the bleachers surrounded by friends, heard his own voice on the loudspeakers crooning “At Fenway,” his tribute tune to Fenway Park in its 100th year.

The catchy melody that Frank Sinatra might have sung if he’d been a Sox fan, was offered by Evans to the Red Sox last fall. It was lost in the quagmire of administrative vetting and paperwork for months, but has been blasted by stadium workers during Red Sox home games for about a month now.

But in spite of its long journey from studio to stereo, when “At Fenway” got to the plate, it hit in a big way.

The Sox love it. “It seems really fitting as we celebrate Fenway Park’s centennial,” says Zineb Curran, Red Sox director of corporate communications. “We appreciate the different ways all our fans try to honor the club. So it’s a great year for the song.”

The National Baseball Hall of Fame has added it to its library. And Major League Baseball licensed the song for game use — a first for the league.

“That part of it has been surreal,” Evans says. “Them making it an ‘official’ song is really very cool, and c’mon, it would be for any Red Sox fan. I’d say it’s one of the best things that’s ever happened for my career.”

That career? If you haven’t guessed: big band singer. Think Sinatra, Tommy Dorsey, Benny Goodman, Duke Ellington. And if you get those voices, then you get the music that the 42-year-old Brian Evans makes.

But in order to get why Evans — whose biggest fans call “The Croonerman” — would declare a locally popular baseball tribute his best professional moment on the same day he released a full-length album that was a hit on two continents, you have to understand his roots.

The short of the story: Evans loves the Sox and has loved them since he was a kid, when only the most faithful loved the Sox and their then-losing ways. He loved the Sox, because like himself, he felt the team was sort of outcast. It was a perceived kinship that helped him get through a very tough childhood.

“Lots of people had tough childhoods,” Evans says. “For me, mine was issues between my parents, who ended up divorcing when I was pretty young. But the upside — I guess there were a few, really — was that my mother and my grandmother who raised me always played big band music. And I fell in love with it pretty early. Also, even though I was definitely not a popular kid, I found comfort at school in a teacher who became a father figure to me.”

That teacher was Frank Delaney, Evans’s now-retired 6th-grade teacher at Nettle Middle School in Haverhill, where Evans grew up.

Delaney says that Evans was a bit of a loner in elementary school but found in big band a musical match for his old soul.

“Brian was a lonely kid,” Delaney says. “He had a lot of things on his mind. Other kids took comfort in light things — games, toys, pop junk, Brian loved good music. And he didn’t love big band just because it involved loud instruments. He appreciated the quality of the music and the soulfulness of the singing. He fully embraced it. And he sang those songs. And many kids didn’t like it. You know how kids can be.”

But by 16, Evans had shed the sadness and moved to Hollywood, where he spent nearly a decade appearing on some of the most popular TV shows of the 1980s and ’90s, including “Full House” and “Beverly Hills 90210.” He costarred in “Book of Love,” a feature film directed by Robert Shaye, founder of New Line Cinema. And according to best-selling author Andrew Morton’s biography of Angelina Jolie, she and Evans dated during his Hollywood swing. A coy Evans will only say, “She’s a great lady. And we were close for a short while.”

“I’ve been proud no matter what he’s done. But all the while though, Brian had his music on his mind,” his mother, Helen Bousquet, says, adding that pining for his music forced Evans to a “sort of crossroads.”

Evans says he attended a charity event featuring Frank Sinatra in 1991. And it was the first and only time he’d meet his childhood idol.