Whether acting, directing or generally living his life, George Clooney comes across as a smart and serious guy with a fun side.

“Leatherheads” is all about the fun. Clooney stars in and directs this homage to screwball comedies of yore and his affection for such classics as “It Happened One Night,” “Bringing Up Baby” and “His Girl Friday” is obvious.

This outing may not grow into classic stature but it’s for the most part amusing and it showcases Clooney’s ability to construct a commercial entertainment.

He plays Dodge Connolly, an aging pro football player in the fledgling days of the sport. Dodge plays for the Duluth Bulldogs, an underdog team that can afford only one pigskin. The time is the 1920s and professional football is barely scraping by, overshadowed on the national scene by college football. The Bulldogs are dismantled but Dodge has an inspiration. If he can land the biggest college star, he can build an audience for the sport and save the team. That star is Carter “The Bullet” Rutherford, a war hero who returned to his college sport after WWI. John Krasinski of TV’s “The Office” plays Carter.

Money talks and Carter becomes the Bulldogs’ star and their ticket to winning games. However, trouble is afoot and it comes in the form of Lexie Littleton, a star reporter. A source tells Lexie’s editor that Carter isn’t what he seems and Lexie, played by Renee Zellweger, is assigned to the story.

Predictably, Carter and Dodge fall for the reporter and much smarty-pants repartee ensues.

Sports Illustrated writers Duncand Brantley and Rick Reilly wrote the screenplay and they provide a subtext that fits Clooney’s rebellious nature down to the ground. Pro football is changing and Dodge is a throwback. As money comes into the sport, so do rules and regulations and consequently out goes the rowdy fun. The writers’ lines are sometimes clever, but not always. Still, the actors deliver each and every one with a determined glib snap. As for the romance, there’s more chemistry in the sparring than the sparking.

Clooney, the director, does not hog the camera for Clooney the actor. He spreads the wealth among his co-stars and the enjoyable supporting players. His major problem is trying to sustain an antic mood for nearly two hours. Some of the slapstick becomes wearisome but it always has Randy Newman’s vintage jazz score to enliven the proceedings.

“Leatherheads,” like a majority of Superbowls, fails to be memorable. But it’s an agreeable way to pass the time.