Dom Dwyer, a former star striker for Sporting KC, gave Atlanta a two-goal cushion with his first goal in 2 1/2 seasons. That proved to be the game-winning goal, as Daniel Salloi converted off a corner kick by Felipe Hernandez in the 85th minute. Caleb Wiley iced it for Atlanta in the 89th minute.
Sporting KC, which had the second-most goals in MLS last season, had trouble with its aim. Only two of SKC's 14 shots were on goal, including Salloi's one-timer.
Sporting KC lost midfielder Uri Rosell with an apparent hamstring injury early in the second half. Rosell was part of Kansas City's 2013 MLS Cup championship squad, but he left the club following that season and returned this past offseason.
Atlanta was the aggressor early, maybe to a fault, picking up a pair of yellow cards for bad fouls in the first 11 minutes. Miles Robinson earned his first card of the season after elbowing Johnny Russell in the third minute, and Osvaldo Alonso earned one when he took the feet out from under Logan Ndenbe.
Araujo pulled up with an apparent hamstring injury. He limped for a couple of minutes before being was subbed off in the 26th minute, replaced by Dwyer.
Sporting finally was able to mount some offense about a half-hour into the match, but to no avail, missing on several attempts inside the box. Then, in the third minute of first-half stoppage time, Martinez found Dwyer one-on-one deep in SKC territory. Dwyer eluded Sporting's Andreu Fontas, then fired a left-footed blast past Melia.