TORONTO -- Movie star Ewan McGregor says he was inspired by Danny Boyle as he called the shots on his directorial debut "American Pastoral."

The Scottish star says he felt nervous moving into the director's chair for the big-screen adaptation of the Philip Roth novel, in which he also stars.

But he was confident in his abilities to tackle the job, also calling the challenge of juggling acting and directing "seamless."

"I've always believed in myself as a filmmaker, anyway," McGregor told a press conference at the Toronto International Film Festival on Saturday, the day after the film made its world premiere.

"I think as actors we are (filmmakers). We don't just get wheeled out of our trailer and onto set to say our words and wheeled off again. We are filmmakers, we are part of filmmaking and so I was pretty sure that I had enough experience to be able to carry it, I think. But of course you don't really know until you're there."

The '60s-set film traces a "perfect" American family that is torn apart by the social and political upheavals of the era.

Seated alongside actresses Jennifer Connelly, Dakota Fanning and Uzo Aduba, McGregor said he was inspired by all the filmmakers he's worked with over the decades, but admits to cribbing one idea from his "Trainspotting" boss.

"And that was about rehearsing with the actors, alone on the set before shooting," he said.

"It sometimes is missed out in the process, it can be seen to be a waste of time, but I know as an actor that when you walk onto a set and you haven't rehearsed it and you're shown a tape on the floor and you're told, 'This is where you start and you're going to sit down on that chair over there when you say this line,' my reaction always, verbally or not, is 'How do you know?' Because I want to be part of making those decisions."

McGregor said "he lived in the novel" in preparation for the task, and was relieved to hear that Roth has given the film his stamp of approval.

"It was a huge relief. I hadn't realized how much I had been carrying the fear of maybe the fact he wouldn't like it because it was very important to me to feel that we captured the essence of his novel."

The Toronto International Film Festival runs through Sept. 18.