'Harry Potter' Cast Reveal The Secrets Of Quidditch

'You're literally sitting on a broom and it gets a little bit sore down under a bit,' actor Rupert Grint says.

Quaffles, Bludgers, Golden Snitchs, Beaters, Seekers, Chasers ... to some this is utter gibberish, but to "Harry Potter" fans these are the beloved elements of Quidditch, the premier witch-and-wizard sporting event in the world. The terminology is peculiar, the rules are myriad and the history stretches back centuries, but all you need to know is that Harry and his pals play by riding around on broomsticks, competing for points and trying to capture that elusive Snitch.

Yet in 2007's "Harry Potter and the Order of the Phoenix," the Quidditch chronicles present in J.K. Rowling's book were cut from the film. On July 15, the game will make a glorious return to the big screen in [url id="http://www.mtv.com/movies/movie/307087/moviemain.jhtml"]"Harry Potter and the Half-Blood Prince."[/url] When MTV News had a chance to visit the U.K. set and talk to the stars about the sport, they revealed the difficulties of filming Quidditch and how the game can sometimes become a divisive issue between the competitive classmates (reader beware: Spoilers exist below).

Emma Watson, who plays the brainy Hermione Granger, told us about a scene in the film in which her character believes Harry (Daniel Radcliffe) has slipped a magical good-luck potion, called Felix Felicis, into Ron's (Rupert Grint) drink before an important match.

"She definitely disagrees with Harry putting the Felix Felicis in Ron's drink because it's the equivalent of taking steroids before a match or for athletics," Watson explained. "She really disagrees with it, but then she finds out that Harry's actually been smarter than her and it's all a psychological thing."

That's because Harry doesn't actually put the potion in his drink — Ron just assumes he's been dosed and thus plays spectacularly. "It's kind of like a placebo drink," Watson said. "So it's all OK in the end."

For Grint, who plays Harry's buddy Ron, "Half-Blood Prince" gave the actor his first opportunity to engage in some cinematic Quidditch. "I was actually really gutted last year because that is sort of Ron's big Quidditch moment and I was really upset they didn't have that in ['Order of the Phoenix']," he said. "I was really looking forward to doing it this time, but it's actually sort of an anticlimax because it's really hard work.

"You're on a broom for a long time, like a few hours at a go," Grint grinned. "You're literally sitting on a broom and it gets a little bit sore down under a bit. It's been fun, but it's quite hard work."

Check out everything we've got on "Harry Potter and the Half-Blood Prince."

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