Diaz Arce scored in the 39th minute on assists from Bobby Convey and Etcheverry to give United the lead. Etcheverry played a square ball from the right flank to Convey in the central midfield approximately 40 yards from goal. Convey served a beautiful chip with backspin over a pair of Arnett Gardens defenders near the top of the box for Diaz Arce, who shrugged off the defenders and slotted a seven-yard shot past goalkeeper Julian McLeish.
A dangerous player on set pieces, Carey Talley struck in the 59th minute on a set piece to push the United lead to 2-0. Etcheverry once again orchestrated the assault, serving a free kick from the left flank towards the top of the box. Ryan Nelsen nodded a flick to Talley, who blasted a 14-yard shot with pace inside the right post.
Diaz Arce provided the final margin with a penalty kick in the 66th minute. The spot kick was awarded after Convey played a cross into the box for forward Chris Albright, who was creamed by the onrushing McLeish, who was off his line to challenge for the 50-50 ball but seemed to forget about needing to play the ball.
United played keep-away with Arnett Gardens over the final 10 minutes of the match seal the victory.
Etcheverry appears to be a rejuvenated player for United after playing through a sub-par 2000 campaign. "El Diablo" spent two months on loan to Bolivian side Oriente Petrolero in February and March, and appears to have regained the form that made him an MLS player of the year and all-star. Etcheverry shredded the Arnett Gardens defense all afternoon with pinpoint passing with precise pace. Etcheverry was so dominant that by the time rookie Bryan Namoff came on for him in the 78th minute, an appreciative crowd of over 4,500 gave the Bolivian a rousing standing ovation as he exited the pitch. After the match, Etcheverry spent 15 minutes posing for photos with dozens of ballboys, fans and media on the field.
United will host Arnett Gardens next Wednesday at 8:00 p.m. at RFK Stadium in the return match. Arnett Gardens will need a four-goal victory over United to advance in the competition.
DC - Raul Diaz Arce (Bobby Convey, Marco Etcheverry), 39.
DC - Carey Talley (Ryan Nelsen, Marco Etcheverry), 59.
DC - Raul Diaz Arce (penalty kick), 66.
D.C. United: Mark Simpson; Craig Ziadie, Carey Talley, Mark Watson, Eric Denton; Brian Kamler, Ryan Nelsen, Bobby Convey (Jose "Chino" Alegria 68'), Marco Etcheverry (Capt.) (Bryan Namoff 78'); Chris Albright (Santino Quaranta 68'), Raul Diaz Arce.
Arnett Gardens: Julian McLeish; Eugene Barnes, William Richards, Kevin Eldemire; Cornel Chin-Sue (Leroy Smith 70'); Jermaine Benjamin (Jonathan Williams 63'), Gerald Neil, Fabian Davis, Kwame Richardson (Byron Earl 68'); Kevin Wilson, Denton Shedden.