By Neil Smith
Entertainment reporter, BBC News
Hollywood pundits are already writing off George Clooney's latest comedy Leatherheads after it failed to top the US box office chart on its first weekend on release.
If its director and star was disappointed by its performance, however, he certainly did not show it during his promotional visit to London this week.
Leatherheads marks Zellweger and Clooney's first film together
Co-star Renee Zellweger was no less ebullient, declaring herself to be a "huge fan" of her on-screen leading man.
Was it difficult, though, to be directed by a fellow actor? Not at all, the 38-year-old told BBC News.
"When he was behind the camera he was my boss, and when he was in front of it he was my co-star. It was seamless," she said.
"He must have been really tired, but my only experience was it felt normal. I was working with a talented person in both respects."
Clooney was quick to return the compliment. "It's fun to work with people you really like, and Renee has been a good friend of mine for years," he said.
"She also has an incredible ability to walk into a period piece and just be impeccable."
Having just been directed by Ed Harris in new western Appaloosa, Zellweger has had more than one experience of seeing a co-star behind the camera.
So do actors make good directors? "In my experience, yes," said the Cold Mountain Oscar-winner.
"They know how to communicate what it is you need to hear as an actor, in order to translate what it is they're looking for."
The film is a romantic comedy set during the Roaring Twenties
What Clooney was after, she said, was a screwball comedy in the tradition of such vintage classics as The Philadelphia Story and His Girl Friday.
"He wanted to do an old-fashioned film where the storytelling was simple and witty and stylistically very different from what it is today.
"And I'm glad, because it was a lot of fun to play around with."
That said, the Bridget Jones's Diary star did find the script's quickfire patter initially hard to master. "You could not drop those lines," she admitted.
"When you do, you let the air out of the balloon and all the tension between the characters is lost.
"It's about giving as good as you get and hitting the ball back."
Set in middle America in the early days of professional American Football, Leatherheads tells of a struggling team facing imminent collapse.
Hiring a popular college player enables Dodge Connolly (Clooney) to stave off disaster and raise his squad's profile.
But it also brings him into contact with Lexie Littleton (Zellweger), a feisty reporter out to expose his latest recruit as a fraud.
It tells of a American football team struggling to make ends meet
Clooney said he extensively rewrote much of Duncan Brantley and Rick Reilly's original script and that he had Zellweger in mind for the main female role.
His attempts to have a writing credit on the film, however, were dashed when the Writers Guild of America's arbitration panel ruled against him.
The 46-year-old has since downgraded his membership, forfeiting his right to vote and attend meetings.
Ask to clarify his position, however, he denied he bears any lasting enmity towards the union.
"It's not an issue for me," he told the BBC News website.
"It's just one of those things where you go, 'If that's the way you feel about it, perhaps I should lodge some form of protest."
Leatherheads is out in the UK on 11 April.