Flames light up participants during introductions at the Professional Bull Riders World Finals at the Mandalay Bay Events Center on Friday night. The seven-day competition continues today at 6 p.m. Photo by John Locher.

So it's your first time attending a professional bull riding competition?

Well, pardner -- yep, it's OK for wannabe cowboys to use that word -- there are a few things you should know.

Actually, even more seasoned veterans of one of sports' most physically demanding competitions might learn a thing or two from this behind-the-scenes look into the world of bull riding:

PROTECTIVE VEST

To help protect themselves against animals that weigh between 1,200 and 2,200 pounds, nearly every rider wears a protective vest, which was invented by Cody Lambert and introduced to the PBR in 1994.

The vest, made of a material similar to Kevlar -- a substance used to make bulletproof vests -- protects the torso from punctures and cuts inflicted by hooves, horns and fences.

"My main goal was to not have to try to ride with broken ribs," Lambert, the Professional Bull Riders' livestock director, said before Friday night's start of this year's PBR World Finals at Mandalay Bay. "I rode bulls for a living and I could do a better job for my family if I wasn't as sore."

FLANK STRAP

One of the most common misconceptions about bull riding is that the rope -- or flank strap -- that is wrapped around the bull's midsection is tied to the animal's testicles.

Nothing could be further from the truth.

"That would be a good way to make the bull stop or lay down," Lambert explained. "If somebody tied something around your testicles, you wouldn't want to be athletic, jumping in the air and moving all over the place. You'd go into the fetal position.

"You can't inflict pain on them and expect them to perform. They've got to be comfortable to be at their best. If it hurts, they'll quit."

The cotton rope, which is sometimes lined by fleece, is tied around the bull near its hind legs, in front of its hip bones, and its purpose is to enhance the natural bucking motion of the bull.

The strap is loosely slipped onto the bull when it enters the alley to the chute. The slack is taken out of it before the ride, but not tied too tight, and the strap is removed immediately after it.

"It's on for 10 or 15 seconds," Lambert said. "You could leave it on him all day and it wouldn't hurt him."

Lambert, a former bronc and bull rider, said a bull wearing a flank strap is akin to a person wearing a belt.

"Unless you're a teenager," he said.

SPURS

Like the flank strap, spurs aren't harmful to bulls, either.

Bull riding spurs help the cowboy stay in position on a bull and maintain his balance by giving him added grip with his feet, and riders can earn extra style points by spurring a bull. But the spurs must be dull so as not to injure the bull's hide, which is seven times thicker than a human's skin.

"The spurs are not allowed to be sharp enough to wound a bull," Lambert said. "If spurs cut a bull, riders are fined and disqualified."

ATHLETIC CUP

Surprisingly, not a single PBR athlete wears an athletic cup, opting, instead, for spandex bicycle shorts and/or athletic supporters.

Mike Lee, who won Friday's first round with a 90.25-point ride on Shane, said he wears a vest, helmet, shin guards and knee guards, but not a cup.

"It's just awkward. It would be in the way," he said. "I tuck my shirt in over it and just kind of tuck it away and hope everything's OK."

FIRST-ROUND RESULTS

OK, greenhorns, on to the first night of competition:

Lee, who won the PBR World Championship and PBR World Finals title in 2004, entered this year's finals in third place in the season standings, but moved up to second place with Friday's win. He trails leader Guilherme Marchi, 10,291.25 points to 8,625.25.

Each cowboy can earn 6,500 points in the finals, including a 2,500-point bonus to the event champion.

Marchi scored 89.25 points on 3 Spot in the first round to tie for fourth place with Robey Condra, who covered Smiley.

L.J. Jenkins scored 90 points on Black Smoke to finish second and Cory Melton scored 89.5 points on Rapid Fire Exchange to place third.

Twenty-five of 49 riders successfully rode their bulls in the first round, including the final nine riders of the night.