Monday, July 12 2010 - David Yates has revealed that Daniel Radcliffe and Emma Watson were in competition with each other when filming a chase sequence for Harry Potter And The Deathly Hallows.

In the "exciting sequence" previewed in the recent trailer, the trio attempt to avoid capture by Snatchers.

The director said during behind-the-scenes footage premiered on ABC: "They run like maniacs and it's because they are trying to out-compete each other.

"Dan wants to run faster than Emma. Emma wants to run faster than Dan and Rupert [Grint] just wants to be anywhere to try to keep up with the pair of them," Yates joked.

"I didn't realise it was going to be that fast actually, I was just keeping up with Dan and Emma," Grint said.

Radcliffe then challenged his co-star to a race at the movie's premiere.

"I'm faster than Emma, I could beat her. There's not even a question in my mind. Red carpet - next premiere, we'll have a race," the 20-year-old said.

He added: "I consider myself to be in relatively good shape but this film could make me a lot fitter and healthier because it's some serious running, climbing, jumping, everything!"

Part one of the final Potter instalment will open in cinemas in November.