Well, here’s an unexpected pleasure of the beer and sweat-drenched variety.

“Golden Arm” is a brassy, scruffy comedy set in the truck-stops, honky-tonks and BFE “civic centers of arm wrestling. The hook? They’re all women, and they’re all funny. The details about the sport and punch-out bar fights that come with it are more entertaining than anything in Stallone’s last-millennium mess “Over the Top,” because “Golden Arm” is a lot more over-the-top.

The catch? You’ve got to buy into skinny-mini Mary Holland (“Veep,” and “Between Two Ferns: The Movie”) as a “contender.”

Holland, just a simple dye-job away from passing for Kristen Wiig’s sister, plays Mel, a newly-divorced baker and small-business pushover recruited by Danny “the Dominator” (Betsy Sodaro of “Disjointed”) to take her place in the Big Tournament.

Sure, Mel’s mild-mannered today. But back before Danny was a long-haul trucker and Mel was just dreaming of donuts without selling-out-to-Dunkin, they were college roomies. And Mel could throw down with the best of them.

Danny’s been injured by her nemesis. She needs a “golden arm” to get in there and take down Brenda the Bonecrusher, played by the amusingly-intimidating Olivia Stambouliah.

Mel has to hit something like bottom to even consider this. New divorce papers and red ink in her business aren’t enough. She’s got to be tricked into not “hiding behind that apron like a depressed, underweight Bobby Flay.”

Director Maureen Bharoocha, who films comic bits for Jimmy Kimmel’s late night show, makes this script by the team that gave us TV’s “Love Under the Olive True” (Ann Marie Allison, Jenna Milly) jump out of the gate. That’s because the early scenes are dominated by Sodaro, a beery bulldog in a china shop.

Danny is all impulse and rage and appetites, and she’s tour guide to this underworld of trucking, flashing truck-stops “for good luck,” grimy sex, arm wrestling and brawls. She schools Mel — and us — hilariously in the do’s and don’ts of her tribe.

“Three ways to get into a bar fight…the classic ‘Just trip’em. BOOM. You’re in a bar fight. Two, steal someone’s beer or their DUDE. And three, the mean and simple ‘flick’em in the head!”

Mel was good at arm wrestling in her younger days. We’re mean to buy into kneading dough has kept her in fighting trim. Because she’s an arm wrestling savant.

The ladies get chased out of rowdy Randy’s bar, played by “Office” man-killer/man-eater Kate Flannery, and get Mel trained by Big Sexy. Dot-Marie Jones matches Sodaro, excess for comic excess in that role. Big Sexy she doesn’t want to train this “jellyfish.”

“Her whole aura is piss yellow!”

Big Sexy teaches Mel and the audience the rules and the pitfalls of this sport, the mere “eight pounds of pressure” that it takes to “break the radial humerus bone” if you put your arm in the wrong position.

Truth be told, “Golden Arm” loses a lot of steam when the ladies get to Oklahoma City for the Big Tournament. This movie’s laughs are on the road, with Randy sassing her old rival Danny for the company she keeps.

“You gonna let Kate Middleton over here tell you what to do?”

Mel is put down every which way by everybody she meets. “American Girl Doll” and “I’ve seen bigger biceps on balloon animals” are two favorites.

Sodaro and Holland have good chemistry in the trucking scenes, which mainly feature meek Mel deferring to Danny’s blue collar brio. Sleeping arrangements in the truck?

“The rule is, ‘Guests have to be the Big spoon.'”

All you want out of a comedy like this is that it begins and ends well, and doesn’t waste a lot of time during the inevitably deflating (romantic interest, tournament) middle acts.

“Golden Arm” and its winning cast are just over-the-top enough to come off

MPA Rating: unrated, violence, profanity, sexual situations

Cast: Mary Holland, Betsy Sodaro, Olivia Stambouliah, Dot-Marie Jones and Kate Flannery

Credits: Directed by Maureen Bharoocha, script by Ann Marie Allison, Jenna Milly. A Utopia release.

Running time: 1:31