United is enjoying an impressive 4-1-2 run as it welcomes a Dynamo side missing Brad Davis, Boniek Garcia and Ricardo Clark.
While the Dynamo are without midfielders Brad Davis (USA) and Boniek Garcia (Honduras), United will boast the services of striker Eddie Johnson, who last week was controversially left off U.S. coach Jurgen Klinsmann's 30-man World Cup roster.
Johnson responded to the snub by scoring his first goal in a D.C. uniform in a 1-1 draw with Montreal on Saturday. The result brought United to 4-1-2 in its past seven games heading into Wednesday's clash at RFK Stadium (7 p.m. ET, MLS Live).
The Dynamo, on the other hand, are enjoying a 3-1-1 stretch, including a 1-0 win over the LA Galaxy this past weekend.
Houston also will be missing midfielder Ricardo Clark (concussion), while United right back Sean Franklin (foot) is questionable.