At 17, Joseph Mahaffey and Carlos Cobb were two gifted high school student-athletes with real prospects for the future.

At 22, both are serving long prison sentences for armed robbery.

"Both of them could make it in the world," said Gainesville High School head football coach Bruce Miller, who coached Mahaffey and Cobb when they played for the Red Elephants in 2002 and 2003. "They had great personalities. Both are very smart kids."

On Wednesday, Mahaffey, a former standout running back who once rushed for 163 yards in a game against North Hall, was convicted by a jury of armed robbery. Hall County Superior Court Judge Jason Deal sentenced Mahaffey to 17 years in prison for the September 2006 armed robbery of a Metro PCS store.

In May, Cobb, who played a key role as a defensive back in the Red Elephants' 2002 trip to the Georgia Dome in the Georgia high school football playoffs, pleaded guilty in federal court to acting as a lookout in the December 2006 armed robbery of the Hall County Credit Union on Limestone Parkway.

United States District Court Judge William C. O'Kelley sentenced Cobb to eight years and two months in prison.

"It just breaks your heart, because these are kids who were just led astray by the wrong people," Miller said.

Mahaffey and Cobb were not charged for the same crimes. But one thing the two had in common, besides having played on the same football team, was their association with James Lamar Chester.

Chester, 23, was admittedly responsible for a late 2006 armed robbery spree in Gainesville. He has pleaded guilty to four armed robberies and testified this week in Mahaffey's trial that he committed at least six.

Chester, who Assistant District Attorney Wanda Vance described to jurors as "a scary person," enlisted Mahaffey's help in the phone store robbery and recruited Cobb in the bank robbery.

Chester is serving a 15-year sentence in federal prison after pleading guilty to the latter.

Mahaffey was convicted of entering the phone store wearing a mask, while Chester, also wearing a mask, threatened employees at gunpoint.

Some store employees cowered on the floor crying, terrified they were about to be killed, Vance said.

Mahaffey rifled through drawers filled with cell phones and may have had an employee open the cash register, according to court testimony.

In the other case, Cobb admitted to acting as a lookout while Chester held a gun to the head of a bank employee and demanded money. The robbers made off with $7,200, according to court records. Cobb and another conspirator were arrested by police the same day.

Miller and others who know the two young men are puzzled by their actions.

"These are not bad kids," Miller said. "They're kids who have made poor decisions. We're talking about two kids who could have gone to college, played athletics and come out with a degree."

"It all comes down to choices," Miller said.