Birchall, in his sixth game after being signed in May following three seasons with Los Angeles, ran past the D.C. line to take a leading ball from Jairo Arrieta. Birchall dribbled down the left side and scored from 10 yards out with his left foot for his first goal with the Crew (7-7-4).
Columbus goalkeeper Andy Gruenebaum made three saves for his seventh shutout.
United (10-7-3) missed a chance to tie the match in the 88th minute when Chris Korb struck the left post with his 18-yarder.
By Douglas Holtz-Eakin
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