Khiry Shelton and Robert Voloder posted a pair of personal firsts to lift Sporting Kansas City to a 3-0 victory over D.C. United on Tuesday night in Kansas City, Kan.Shelton scored his first goal of the season in the 34th minute and Voloder added the first goal of his career in the 70th to help keep Sporting KC's faint playoff hopes alive.Sporting KC (9-15-7, 34 points) still must win their remaining three matches and have Real Salt Lake lose their remaining four matches to have any chance at the postseason.D.C. United (7-18-6, 27 points) had already been eliminated from postseason contention before the match.With traffic clustering in front of the D.C. United net, Voloder fired a left-footed shot that D.C. keeper David Ochoa barely saw. Sporting KC spent much of the second half on the front foot, sending 11 more shots at Ochoa.Daniel Salloi erased any doubt with a thunderous right-footed shot from just outside the box in the 87th minute.Sporting KC had a season-high 12 corner kicks.With many of their top offensive threats starting the match on the bench, Sporting KC broke in front in the 34th minute when Marinos Tzionis crossed from the right wing and found the foot of Shelton, who redirected it into the net.Shelton, who has started 15 matches this season, has seen much of his participation taken by summer addition Willy Agada.Nursing a 1-0 lead, Agada and Johnny Russell entered the fray in the 61st minute, joining Erik Thommy and Felipe Hernandez who came in at the start of the second half.Sporting KC controlled everything about the first half. They held 58 percent of the possession and outshot D.C. United 6-2 with the only two shots on goal.Sporting KC goalkeeper Kendall McIntosh made his MLS debut at age 28. He finished with two saves. Both were on shots from close range.--Field Level Media