You have to give George Clooney credit for ambition, if not necessarily execution, in the films he directs. His debut feature, “Confessions of a Dangerous Mind” (2002), was a weirdly surrealistic mess, but it certainly made an effort to be different. Things worked out far better in “Good Night, and Good Luck” (2005), a superbly evocative treatment of Edward R. Murrow’s television confrontation with Senator Joseph McCarthy. But his third outing, “Leatherheads,” turns out to be, despite its visual panache, surprisingly pallid in most other respects—laxly paced and narratively muddy. In this old-time football saga Coach Clooney gets sacked.

Clooney’s goal in this case is to replicate a classic screwball comedy in the style of Capra, Sturgess or Hawks within the context of a nutty narrative set against the backdrop professional football’s birth as an organized sport. In 1925 Minnesota, Clooney is Dodge Connolly, the con-man player-coach of the Duluth Bulldogs, a rowdy bunch of locals so impoverished that they can’t even afford more than a single pigskin. To save them from bankruptcy, Connolly recruits for the team Princeton star Carter “The Bullet” Rutherford (John Krasinski), not just the greatest celebrity in college ball but a certified hero of World War I, whose services Dodge secures by promising the boy’s smoothly mercenary agent (Jonathan Pryce) a large slice of the predictably huge gate receipts.

Unfortunately, Lexie Littleton (Renee Zellweger), star reporter for the Chicago Tribune, enters the picture with the assignment of exposing Rutherford’s war record as a fraud. A tart-tongued, hardboiled broad who might once have been played by Barbara Stanwick or Rosalind Russell, Lexie gets close to Carter, eventually luring from him a confession that his Sergeant York-like act of heroism was actually more like a misconstrued act of cowardice. By this time, of course, a typical love-hate relationship, marked by sharp verbal sparring, has developed between her and Dodge, which will cause a rift between Connolly and Rutherford. When Lexie’s story comes out, moreover, it creates a scandal that’s resolved only with the appointment of a football commissioner and the creation of a rulebook for the game, which marks the end of the anything-goes play of Dodge and his like and the transformation of the sport into the business operation it’s now become.

The script by Duncan Brantley and Rick Reilly works hard to meld the conventions of the whiplash comedies of the thirties and forties with a lighthearted sports origin scenario, but the combination never takes wing. For one thing, many of the one-liners exchanged by Dodge and Lexie have a recycled feel. (And showing them having an early insult match in a Pullman car is entirely too reminiscent of “It Happened One Night.” It’s never a good idea to remind viewers of a picture so much better than your own.) For another, the chronology is off. The story is supposed to be happening in 1925, but the suggestion seems to be that the war’s still on, with doughboys still being “shipped out” for some reason; and Rutherford, who’s said to have interrupted his studies to serve, is described as a junior, though the war actually ended seven years earlier.

Most seriously, though, the resolution of the plot is problematic. Simply put, the treatment of Carter in the latter reels feels needlessly cruel. As played by the engaging Krasinski, he’s a likable lug who might have made some mistakes but regrets them, and is genuinely nice to others—only to have them reciprocate by trying to destroy him—and the fact that they’re presented as the ones you’re supposed to root for is off. As if that weren’t enough, the big game in which the picture inevitably concludes is a letdown, and the underhanded play that decides it is bungled in the telling, so that it’s hard to discern exactly what’s going on. Not that you care much; by that point little comedic yardage has been made, and it’s impossible to have much emotional investment in the outcome.

The performances aren’t all they should be, either. Krasinski’s boyishness comes off well and both Stephen Root and Peter Gerety earn some laughs as a hard-drinking reporter and the new commissioner. But Clooney overplays his roguish charm (he might have been better under a director other than himself—someone else could have infused greater energy into the whole film, in fact), Pryce is tediously sleazy, and Zellweger, twisting her lips in a kind of sophisticated sneer, is all studied attitude. Admittedly it’s a difficult sort of role to pull off; Jennifer Jason Leigh had trouble with a similar one in “The Hudsucker Proxy.”

Mention of that 1994 picture even shows the deficiencies in “Leathernecks” where it’s strongest—on the visual side. Jim Bissell’s production design, the art direction by Christa Munro and Scott T. Ritenour, the sets by Jeff B. Adams, Thomas J. Minton and Jan Pascale and Louise Frogley’s costumes are all first-rate, as is Newton Thomas Sigel’s luscious cinematography. But compared to the luxurious period look that the Coens achieved in the earlier film, Clooney’s picture is at a distinct disadvantage.

As with “Confessions,” ambition isn’t enough. “Leatherheads” succeeds neither as a paean to the rambunctious football of the old days nor as homage to the great screwball comedies of Hollywood’s yesteryear.