D.C. United entered their third season as the two-time defending MLS Cup champion, as well as the defending Supporters' Shield titleholder. Finishing as runners-up in MLS Cup '98 and second-place in the regular season standings, United failed to defend both domestic honors. In international play, D.C. United made American soccer history, becoming the first American soccer club to win any CONCACAF club tournament, being the 1998 CONCACAF Champions' Cup. It was only the third time in CONCACAF history that an American soccer club reached the Champions' Cup final (previously achieved by Los Angeles Galaxy the previous season and New York Pancyprian-Freedoms in 1984). Since their title, only the Galaxy have won the Champions' Cup, which they accomplished in 2000, and it would not be until 2011 when Real Salt Lake reached the 2011 CONCACAF Champions League Finals would an American club once again reach the North American club final.

D.C. United ended their sophomore campaign on a high note, claiming the "league double", earning both the Supporters' Shield (regular season), and the 1997 MLS Cup championship (postseason). During the 1997 campaign, the club nearly earned a tuble, which is to win four or more top tier trophies during a single season, but ultimately fell short of that. In the domestic cup competition, the U.S. Open Cup, D.C. United reached the final of the competition, only to lose against Dallas Burn (now known as FC Dallas). In the continental club tournament, the CONCACAF Champions' Cup, United finished in third place, after falling to Los Angeles Galaxy in the semifinals.

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