Luis Silva and Eddie Johnson scored in 2nd half as D.C. extended lead in Eastern Conference to 4 points over Kansas City.
Tim Howard and Everton were buried by Chelsea, while Brad Guzan and Aston Villa remained unbeaten.
Six players are seeking their first cap when the U.S. national team faces the Czech Republic in Prague.
The Washington region is coming off a banner season, in which two men’s and two women’s teams advanced to the respective College Cup semifinals and 10 others earned NCAA Division I tournament berths.
Landon Donovan posts a goal and 2 assists and Los Angeles overwhelms DCU in first half.
With a victory at StubHub Center, United would reclaim the lead in the MLS Supporters' Shield race.
Clubs will play four fewer games, lose national team players for at least seven matches.
The marquee forward is back from suspension, but Fabian Espindola and Luis Silva have played well together.
The dean of American soccer coaches addresses MLS procedures, Landon Donovan, the U.S. national team and Ben Olsen.
U.S. World Cup midfielder was first coveted by Chicago Fire but landed in Foxborough, by virtue of MLS blind draw.