Originally acquired by DC United in the 2005 season the Argentine defender quickly became a mainstay in the team’s back line playing a total of 8 regular season games that season as well as starting in the two playoff matches that the team participated in.
In 2006 the quality of this young player was evident as he started 30 regular season games as well as all 3 playoff matches scoring 3 goals and recording 2 assists from his backline position.
His stellar play in 2006 earned him a start in the MLS All-Star game that year when the MLS All-Stars beat EPL powerhouse Chelsea in Chicago.
This season Erpen has started 11 games for DC recording 2 assists.
Before joining MLS Erpen played for Talleres de Cordoba starting in the 2000 season when the team was a member of the Argentine Second Division. He was a staple in Talleres' backline for five years and helped Talleres gain promotion to the First Division in 2002. During his time with the team Erpen appeared in 58 first division games and notched four goals.
He began his professional career in Argentina as a member of Club Juventud Unida de Entre Rios before spending time with the youth teams of First Division power Boca Juniors.
Greg Vanney who was originally acquired from FC Dallas along with Dallas’ 2008 third round draft pick on January 12 2006 in exchange for the Rapids’ 2007 second round draft pick (18th overall) and the team’s 2008 second round draft pick has played a total of 9 games with the team this season.