Maric stopped four shots for his second clean sheet of the season and fifth of his 29-game MLS career.
Urruti's goal came as the visitors were laying siege to the Houston zone, peppering Maric with shots that were either just off the mark, being blocked by the Dynamo defenders or slapped away by the goalkeeper.
Play in the first half was mostly limited to the middle of the field as neither team recorded a shot on target over the first 45 minutes of play.
Houston led statistically in all the offensive categories, owning a 52.3 percent to 47.78 percent edge in possession percentage, taking 3 shots to just 1 for Sporting KC, forging an 84.8 percent to 81.7 percent advantage in passing accuracy, and spotting three corner kicks to none for the visitors.
Sporting KC was the aggressor in the first minutes of the second half, with Daniel Salloi ripping a shot in the 51st minute that Maric was able to bat away.
Urruti steadied the ball before firing a right-footed shot from the center of the box past Sporting goalkeeper John Pulskamp to the high center of the net. The goal came on the Dynamo's only shot on target in the match.
Houston coach Tab Ramos was shown the red card and removed from the sideline after vehemently arguing a non-call on the Dynamo's Fafa Picault in the 89th minute.