 Opting to forgo his last two years at North Carolina, he was drafted in the first round, 6th overall, of the 2006 MLS SuperDraft by FC Dallas.McCarty made his MLS debut in the 85th minute in a 3–0 loss against Chivas USA on July 1, 2006.Dax had his best season as a professional in 2007 making his first start against the Los Angeles Galaxy in a 2–1 victory on April 12, 2007 and scored his first career MLS goal against the Galaxy on September 23, 2007.