Mapstone came in first in two of the competitions and placed second with teammate Vinnie Winter in another event, a far cry from his amateur days playing in a dart league aboard ship.
All said, the team brought home about $300 in prize money from the dart championship.
Half of the team's winnings from tournaments are donated to the local chapter of the United Way.
Four employees of Phoenix Color and three other players formed a team about two years ago, and the company agreed to sponsor them in dart tournaments.
A popular game played in bars and basements, darts has gained a renewed popularity with the advent of lighter weight soft-tip darts - so-named because of their plastic tips - which are thrown at electronic targets.
The electronic targets, slightly larger than the traditional steel-tip dart boards, have replaced the complicated chalk and blackboard method of scoring by calculating scores automatically and digitally displaying the numbers.
"Soft tip is a lot less intensive. You can have a lot more fun and you don't have to concentrate so much on keeping score," said Shawn Herold, a team member.
The stakes also have improved, with tournaments and competitions now offering more than your usual round of beer to winners, though that's still a popular incentive at practices.
Dart tournaments, like the one in which the Phoenix Color team participated, often pay out $5,000, $10,000 and $20,000 or more in prize money. The national championship series sponsored by the American Darters Association pays out more than $100,000 in prize money.
But it's the challenge, friendly competition, social benefits and travel that have attracted a new generation of dart players.
"I wanted to do something else," said Eric Palmer, who got tired of football and baseball after playing the sports in high school.
After seven years of playing darts, Palmer has proven himself a worthy member of the Phoenix Color team as the 1996 National Dart Champion and the 1997 National Most Valuable Player.
"The biggest attraction to playing darts is that it's nice competition. There's usually no animosity," Herold said.
"That's true until you start playing for a lot of money," added Palmer.