Pro football isn't exactly underexposed on network television. But that doesn't mean that Sunday's ABC movie "Fighting Back" -- on Channel 7 at 9 -- isn't well worth watching.The story of a courageous athlete overcoming a handicap may seem familiar enough, but this one is true, and entertainingly told.

Robert ("Vega$") Urich plays Rocky Bleier, the veteran football star of the Pittsburgh Steelers, who was seriously injured while on duty in Vietnam, and returned to the States with only a reported 50-50 chance of ever walking again. Doctors said his football career was finished.

But Bleier trained like crazy and worked his way back into the Steeler lineup. He is now in his 12th (and final) year as a pro and has become the fourth leading rusher in the history of the Steelers. Not bad for a player referred to by one character as "a cripple."

The possibility of simply trying to create another "Brian's Song" -- a tearful TV movie about a football player and hardship -- has been avoided by executive producer Jerry McNeely, who also wrote the screenplay, and by MTM Enterprises, which has succeeded in other TV movies -- "First You Cry" with Mary Tyler Moore and "Just an Old Sweet Song" with Cicely Tyson.

Aside from a scene where Steeler owner Art Rooney, (Art Carney) calls the team together with a "just-received-word" report on Rocky's injury -- similar to Gale Sayers' speech to his Chicago Bear teammates after it is discovered that Brian Piccolo has cancer -- the movie stands on its own. It brings the game of football into the living room without Hollywood heroics or the myth-popping of movies like "North Dallas Forty" and "Semi-Tough."

This makes for a film that will appeal to a wider audience than just Sunday-afternoon football junkies. Rocky's relationship with a woman (the likable Bonnie Bedelia) whom he meets at a dinner party meshes with the story of his struggle, and rounds out the picture of his life. Bleier wrote the book from which the screenplay was adapted, and had a hand in the production (although the film doesn't come across as self-serving).

The real player and Urich, who plays the part, developed a simpatico relationship that bolsters the credibility of the film. When they appeared together on "Good Morning America" this week, the two carried on like old buddies who respect one another and who each have a sense of what the other's role really is.

Now, no football movie would be complete without a cameo appearance by Howard Cosell, and sure enough, there amidst actual footage of the real Rocky in action, is dear Howard on ABC's Monday Night Football, calling a Rocky Bleier play.

Carney is so good as Rooney, and Richard Herd looks so much like Steeler coach Chuck Noll, and Cosell is such a dead ringer for Cosell, that the actors meld smoothly with appearances by real-life Steelers like Mean Joe Greene. Fred Karlin's music enhances both the love scenes and the action on the field and marks a welcome departure from the usual tinkly tones one hears on TV movie soundtracks.