The romantic rivalries spill over to the Quidditch pitch, where Ron and Cormac McLaggen are both trying out for the Gryffindor Quidditch team. Hoping to catch Hermione's eye, the handsome and athletic Cormac has decided to compete against Ron for the position of Keeper. "He's an arrogant show-off, who thinks he is the best at everything," states Freddie Stroma, who plays Cormac. "He wants to give Ron a hard time by going after the position of Keeper...and Hermione."

"Ron is understandably intimidated by him because Cormac is in a physical class that Ron will never be," says Heyman. "But with some help from his friends, Ron puts Cormac in his place."

Second unit director Stephen Woolfenden reveals, "One thing David Yates really wanted to do was get Rupert up there on a rig and catch him off guard, so we filmed him from a variety of angles where we would just fire 20 Quaffles at a time at him. The real responses to everything flying at him at once made for some very funny viewing and the improvised nature of it also made it easier for him to look as though he is not as in control."

In addition to the team trials, there is also an actual match between Gryffindor and Slytherin. "It was really great to work on the Quidditch scenes, which is something I didn't get to do in the last film," Yates says. "From the start, we wanted to explore how physically demanding a sport it is, because if you're flying around on a broomstick at 60 miles-per-hour, trying to avoid Bludgers and each other, it can actually be quite dangerous. In our Quidditch, you see players colliding in mid-air and falling, so it's visceral and very fast."

"We wanted it to be like rollerball on brooms," adds David Barron. "It's tougher and rougher than Quidditch has ever been before, but also a lot of fun."

Woolfenden says that capturing the rough-and-tumble action of the flying sport "was a wonderful mix of departments all working together: visual effects, stunts, special effects, camera, costumes..."

The flying rigs used for the Quidditch scenes in the previous films had to be redesigned for "Harry Potter and the Half-Blood Prince," mainly because the kids have grown up. Special effects supervisor John Richardson offers, "The broomstick rigs we had in the past were all designed for little kids, and now we're dealing with big, strapping lads and lasses. Everything had to be redeveloped."

There were several different rigs utilized to capture the high-flying action, including one called the Matrix rig, which could rapidly spin an actor or stuntperson on any axis, while keeping them safely secured. Stunt coordinator Greg Powell notes, "It gave us great range of motion in a nice fluid movement, but was very safe."

"They could spin around one way and then the other, and backwards and forwards... It looks great, but I would hate to do it after lunch," Richardson jokes.

Other equipment incorporated to film the Quidditch sequences included: a pole arm, on which the broom could be mounted and either manually or mechanically manipulated; a giant Russian swing, which could literally launch a person into the air, allowing the camera to catch them in free fall; and, of course, a traditional trampoline.

Jany Temime designed new Quidditch uniforms, including a training outfit, which she describes as "basically like a track suit with extra padding on the arms and legs and a leather helmet. The game uniform is obviously more glamorous than the training outfit. Everything was handmade. It was absolutely sumptuous."

Completing the look of the game uniforms, visual effects supervisor Tim Burke and his team digitally added the teams' capes in post-production. They made the capes appear to be streaming, adding to the effect of speed.

Production designer Stuart Craig also updated the look of the Quidditch stadium. "We put in more towers and they're closer together, which offered the players more opportunities for weaving in and out," he explains. "It added to the action with things whizzing by at close proximity. There are also proper bleachers. I think it's altogether more impressive."