Venice acclaims Blanchett's portrayal of Bob Dylan

She is one of Hollywood's most elegant actresses who has won plaudits her ability to carry off the regal gravitas of Elizabeth I, the ethereal quality of Tolkien's Elfin queen and the vivacious charms of the Hollywood star Katharine Hepburn.

But even Cate Blanchett admitted she was "very scared" when she was offered a starring role in a film about the rock legend, Bob Dylan, as the singer himself. Featuring among six actors who portray the iconic Jewish American singer-songwriter in the biopic, I'm Not There, Blanchett is the only woman among them.

But if cynics doubted that the petite, blonde Australian actress might not be able to pull off her role as the gravel-voiced singer, the unanimously glowing reviews of her performance that greeted the film's premiere yesterday will have vindicated her: the toughest of film critics at the Venice Film Festival were tipping Blanchett as a serious Oscar contender for her sensitive portrayal.

Todd Haynes, the cult American film director, chose to include Blanchett in the cast in hope to draw out the numerous faces of the Jewish American musician. Blanchett, who won an Oscar for her portrayal of Katharine Hepburn in The Aviator, plays Jude, a representation of Dylan in the 1960s when he shocked folk followers by embracing amplified rock. In her black-and-white sequences, Blanchett's hair is dark and frizzy, and she adopts some of his unique mannerisms.

Launching the film, which is in competition at the festival, Haynes said he had taken Blanchett on for the role of Jude because he wanted a woman to reflect Dylan's gawky and rather eccentric physical appearance at the time.

"Jude was always meant to be played by a woman. I felt it was the only way to resurrect the true strangeness of Dylan's physical being in 1966, which I felt had lost its historical shock value over the years.

"But of course it would take an actor of Cate's supreme intelligence and ability to bring to the role the kind of depth and subtlety she delivers. Cate was scared; she told me many times that this was a very scary challenge for her. It took her a long time to commit to it, she's a very busy actress and had to balance it with her schedule but mostly I think it was due to fear, which is completely understandable.

"I told her it's good to be terrified, that you're taking a risk and sometimes that's really when the surprises happen. I guess it at least convinced her to give it a shot," he said.

The other actors who play the 1960s singer in Haynes's film are Heath Ledger, Richard Gere, Christian Bale, Ben Whishaw and the black child actor Marcus Carl Franklin.

The film, which Dylan is said to have given his blessing, is the first dramatised production to which the singer is said to have happily consented. There have been numerous documentaries made about his life, including one directed by Martin Scorsese which was released to great critical acclaimed two years ago.

Haynes said Dylan was such a challenging subject who required six representations because of his "complex and contrary" nature. Richard Gere said he had jumped at the chance to play such an icon of the modern age. "I think Dylan is probably the only artist in our time who will still be considered 200 or 300 years from now. It's not Picasso, it's Bob Dylan. No one has had more effect on the world of art" he said.