Mejia, a 2007 second-round draft choice out of DePaul, lost out in his battle for the final roster spot with veteran Ronald Dupree.

The waiving of Mejia means the Pistons will carry three rookies on the roster – first-round picks Rodney Stuckey and Arron Afflalo and Senegalese center Cheikh Samb, a 2006 second-round choice who spent last season playing professionally in Spain.

Mejia’s chance to stick on the final roster took a hit in August when the Pistons spotted an opening to strengthen themselves at small forward after Washington decided not to exercise its option on four-year veteran Jarvis Hayes.

Hayes had a strong preseason, leading the team in scoring at 13.6 points a game and shooting 44 percent from behind the 3-point line. He’s first in line for minutes behind Tayshaun Prince at small forward – the job Dupree had hoped to win when the Pistons traded Carlos Delfino to Toronto in June.

In addition to Hayes, the Pistons believe Afflalo is capable of backing up Prince, which made it a two-man fight for the last spot between Mejia and Dupree.

Dupree, 26, played for the Pistons in 2004-05 before being traded to Minnesota for a second-round draft pick that Detroit is due to collect for the 2008 draft. When the Timberwolves let him go following that season, he signed with the Pistons prior to the 2006-07 season. He played a total of 94 minutes in 19 games last season.

The 6-foot-7 Dupree went undrafted out of LSU but hooked on with the Chicago Bulls, playing 47 games in 2003-04 and making the only eight starts of his NBA career. Regarded as a strong perimeter defender, Dupree’s shortcoming has been the lack of a reliable jump shot.

Mejia, 24, was the 57th overall pick in June’s draft. In six preseason games, he averaged 1.7 points and 2.2 rebounds, shooting 23.5 percent.