PEORIA, Ariz. -- Pitcher Casey Kelly, regarded as the top prospect in the Padres' Minor League system, suffered his first setback of the spring on Thursday morning.

No, it wasn't an injury that felled the 21-year-old, the player the Padres wanted most in the Adrian Gonzalez deal, but more so his pride that took a hit during a team-building exercise drill on a back field at the Peoria Sports Complex.

Kelly, who coming out of high school signed a letter of intent to play quarterback at the University of Tennessee before being drafted and signed by the Red Sox, was edged by pitcher Cory Luebke in a quarterback challenge that was held in front of the players in camp as well as front office staff.

"It was a blast and it's good for team camaraderie," said Kelly, who last took snaps in a game as a high school senior in the fall of 2007. "I was impressed with everyone. As for Cory, he was kind of the dark horse."

Kelly, Luebke and catcher Nick Hundley and second baseman Orlando Hudson -- who were all quarterbacks in high school -- went through a series of throwing drills that had them throwing to teammates at various points on the field.

Clayton Richard, who played quarterback at the University of Michigan, didn't take part in the competition but instead served as the "commissioner," according to manager Bud Black.

The players had to try to hit a moving target -- in this case, a garbage can that was situated on a maintenance cart driving across the field. Yet another toss had players attempting to throw the ball to a teammate seated in the back of another moving cart, as the cart drove away from the players.

Each spring, the Padres go through some behind-the-scenes exercises such as a free-throw contest. Last year, third baseman James Darnell, who played the trumpet in high school, played "Tequila" for his teammates.

Black doesn't typically share the details of these exercises with the public. He had little choice on Thursday, though.

The football drill, brought on when Black wanted to see how "legit" Kelly's quarterback skills were, might well have topped them all, especially with pitching coach Darren Balsley dressed in full football attire for the exercise -- a getup that including full pads and face paint.

Third-base coach Glenn Hoffman acted as a referee, taking pride in signaling if a catch was made or not or if the intended target managed to keep his feet in bounds.

Players cheered after Black declared Luebke the winner by raising his hand. He was then mobbed by his teammates before players separated for their morning workouts.

"We're here for six weeks," Black said. "... We try to do some things to keep the guys going."