Jimmy Nielsen earned his league-leading fourth shutout for Sporting (3-1-2), which has not given up a goal in 429 consecutive minutes and ran its winning streak against D.C. to five matches.
United (1-3-1) is winless in its past three and was shut out for the third time this year.
Nielsen had to make just one save against D.C., which had more yellow cards than shots on goal.
Soony Saad, who entered the game in the 83rd minute, set up Bieler's late game-winner for his first assist of the season. Saad stole the ball from Marcos Sanchez in the left corner, then dribbled between Marcelo Saragosa's legs at the end line before passing back to Bieler.
Bieler struck a left-footed shot inside the right post for his fourth goal since joining Sporting this season from Ecuadorian side LDU Quito.
The game had five cautions issued, three against United and two against Sporting.
- Sports & Recreation
- Sporting Kansas City
- Claudio Bieler
- Jimmy Nielsen