Wives, girlfriends, toddlers, moms — all of them marching in montage-style as music proudly swells before the climactic, do-or-die playoff game against a cocky, over-privileged opponent.

As a football movie about teenage convicts learning discipline in the way of the pigskin, Gridiron Gang falls somewhere between hand-on-throat and finger-down-esophagus. But Camp Kilpatrick’s Mustangs aren’t always roody-poo saps, not when coached by The Rock — forced by the WWE to sandwich his wrestling name within his given one of Dwayne Johnson.

Dwayne’s days as a college-football defensive tackle with the Miami Hurricanes certainly inform The Rock’s convincing portrayal of coach Sean Porter. Posturing and threats are a given, but he delivers a rah-rah speech great solely because his voice is hoarse — something rarely heard in such movies after endless, passionate yelling. And in his first real dramatic role, The Rock’s eyebrows often are cast down in somber contemplations of the kids’ futures. And he even wells up a tear.

It’s a strong return to The Rock’s natural charisma after an ill-advised bad-guy turn in Doom. Coupled with the stern hand of director Phil Joanou (himself back from long Hollywood probation), it’s also Gridiron Gang’s best defense against the usual offense of cliches in based-on-truth films.

The dying parent whose time no doubt will expire before the big-game clock. The villainous team that does backflips in the backfield before calling black Mustang players the “N” word. Long-lost family members showing up at the last moment to offer soulful support glances. Maxims like “It’s a whole new world out there when you earn things.”

Gridiron Gang constantly teeters on becoming a filmed version of a Successories calendar. But The Rock and Joanou yank hard against Jeff Maguire’s heart-tugging dialogue and pull the movie back with gravity and grit in a way that the similarly structured Glory Road tried but couldn’t nail.

As a lineman writes, “I love sacking the quarterback. Sometimes I can’t even believe it’s legal,” in a letter, it’s funny. But, often through unexpectedly violent passages, the movie remembers it’s no second-chance fable, but a story of murderers’ and thieves’ fleeting shot at goals and productivity.

Based on a documentary of the same name, Gridiron Gang fictionalizes probation officer Porter’s 1993 creation of a football program at a Malibu, Calif. juvenile detention center. How fictionalized? Let’s hope assistant coach Malcolm Moore accomplished more than Xzibit does playing him — one comic-relief bit before planting himself firmly next to The Rock, arms folded.

Tired of being sheepherders to fatten the kids up and put them back on the street, Porter and Moore pitch the plan to the powers-that-be and game the system to keep it afloat when it struggles.

Early practices are fights waiting to happen, high-school teams are reluctant to play felons and the first game is a monumental disaster. Eventually, the team puts aside neighborhood beefs to make it 100 yards downfield. But there’s the possibility that Porter’s endeavor could just be emotional cover for his own college-football experience, wounded by a late taskmaster dad.

The football action is well filmed and exciting, but appropriate use of handheld cameras (akin to the superior Friday Night Lights) and borderline R-rated raw language reflects commitment to something a little harder hitting. None of its motivational bits resonates with the simplicity of “Be perfect” (from Lights), and no fictionalized sports movie ever will rewrite the playbook. The fun of Gridiron Gang is a wisely called audible after reading all the corniness lined up against it.