Freddy Adu, the 15-year-old soccer sensation from D.C. United, won't play for the U.S. Under-20 National team in tonight's exhibition match against the Seattle Sounders, according to his Major League Soccer club.

D.C. United won't release Adu for the 7 p.m. match at Husky Soccer Field because he played a total of 90 minutes over the weekend in an MLS game and an MLS developmental-squad game.

"It's a matter of monitoring his playing time," Doug Hicks, D.C. United vice president of communications, said of Adu not being part of the 14-man U-20 roster in Seattle. "He played a half (Saturday) and a half today with the reserve team. We watch his playing time and the wear and tear on him. It's at our discretion to release him to games."

When he was 14, Adu became the youngest player to sign with a top-level team in any U.S. pro sport in 100 years.

Adu was not one of six MLS players listed on the U-20 roster in a U.S. Soccer release. MLS players set to suit up for the match against the Sounders are Chad Barrett and Will John of Chicago, Arturo Alvarez of Dallas, Hunter Freeman of Colorado, Danny Szetela of Columbus Crew and Tim Ward of the MetroStars.

The Sounders open their regular season at Qwest Field on Saturday at 7 p.m. against the Portland Timbers.