By David Germain,AP Movie Writer

Stripped of almost all the brothers’ usual crudeness, “Fever Pitch” proves what we’ve suspected all along: That beneath the gross-out gags and freak-show humor, Peter and Bobby Farrelly are just a couple of lovable romantics.

No doubt it helps that they’re directing off someone else’s material. Especially when it’s actually three someones with a track record in romantic storytelling, screenwriters Lowell Ganz and Babaloo Mandel (“Splash”) and British author Nick Hornby, whose autobiographical book was the basis for the film.

Drew Barrymore is at her most likable as a driven career woman who runs into foul territory when she falls for a man maniacally devoted to the Boston Red Sox. And as the Sox disciple, Jimmy Fallon presents understated charm and cheeriness lacking in last fall’s “Taxi,” his miserable big-screen debut as a lead player.

It all adds up to the most unFarrelly of Farrelly brothers movies, a straight-on romantic comedy that dispenses with the indelicate humor of such flicks as “There’s Something About Mary” and “Shallow Hal.”

In tone, at least, “Fever Pitch,” better resembles “Outside Providence,” the sweet little teen comedy the brothers co-wrote and produced based on Peter Farrelly’s novel, than anything else they’ve done.

As Hollywood did with Hornby’s “High Fidelity,” “Fever Pitch” transplants his book from Britain to America, switching the sports fanaticism to baseball instead of soccer.

Fallon plays Ben Wrightman, who caught Red Sox fever as a boy when his uncle took him to a game at Fenway Park. Ben inherited his uncle’s season tickets near the Sox dugout and never misses a game. His apartment is dementedly festooned with memorabilia – towels, sheets, a shower curtain, even a replica of the Green Monster, Fenway’s outfield wall, in the living room.

A math teacher, Ben meets business consultant Lindsey Meeks (Barrymore) on a field trip with his students. It’s not exactly love at first sight, but Ben’s gentle humor and gallantry soon win Lindsey over.

At least in winter, before opening day. Ben confesses his Red Sox fixation early on, but Lindsey does not realize the all-consuming passion of the sports zealot until the height of summer, when she’s too far into the relationship to back away without getting hurt.

“I already know I like winter guy. It’s summer guy that broke my heart,” Lindsey tells Ben.

The movie runs a bit dull and choppy early on, but the laughs build along with the momentum as the season progresses and Ben’s compulsion mounts.

“Fever Pitch” is so completely Barrymore and Fallon’s show that talented supporting players such as Ione Skye, JoBeth Williams and Willie Garson come off as benchwarmers who never see any meaningful action.

The filmmakers got down in the trenches with the Red Sox and their fans, filming at Fenway both during games and while the team was on road trips. “Fever Pitch” nicely incorporates the sights and sounds of a town reveling in their team and bemoaning their fate as fans of one of the unluckiest franchises in sports.

Blind luck landed the Farrellys at Fenway as Boston actually started winning, the Red Sox finally ending the curse of the Bambino to win their first World Series since 1918.

The filmmakers scrambled to adapt the story, which originally ended with the Sox losing yet again. The Farrellys even managed to sneak Barrymore and Fallon on the field in St. Louis after Boston won the championship last fall.

That gave the filmmakers leeway to go sugary sweet with a fairy-tale conclusion that would have been dismissed as Hollywood fluff had it not actually happened.