Outplayed by a more aggressive FC Dallas in a scoreless first half, the Sounders erupted for three goals in the second, all by substitutes, for a 3-0 victory in front of 41,108 at CenturyLink Field Saturday night. With the win, the Sounders (9-4-2, 29 points) took over the top spot in both the Western Conference and Supporters’ Shield races.

“It was a game of two halves,” said Sounders coach Sigi Schmid. “Dallas was the better team in the first half, but in the second we were much more aggressive and the result was three goals. It’s always important to get your points at home, and this shows our resiliency.”

FC Dallas created enough scoring chances — six shots, two on target — in the first half to come away with, generously, a 2-0 advantage, but couldn’t finish, Its best opportunity came in the 20th minute when Fabian Castillo blasted a shot off the far post.

Schmid subbed in Brad Evans, just returned from national team duty, to start the second half at a midfield slot. His insertion provided the Sounders with an immediate burst of energy.

In the 56th minute, Evans passed to Lamar Neagle, who went to the left side of the penalty area and drilled a 20-yard shot into the far right corner past FC Dallas goalkeeper Dan Kennedy. It was Neagle’s third goal of the year.

Obafemi Martins, wearing a face mask as a precaution after nose surgery, flicked in a spectacular goal in the 73rd, his seventh, on a left-footed shot from six yards out and with his back to the net. Martins, who sat out Seattle’s 1-0 road loss to Sporting Kansas City last week, executed his customary back flip.

“I’m just so excited to be back,” said Martins, who entered in the 66th minute. “I love my job and I’m happy that I’m back with my teammates. We deserved this win and we are happy with the three points at home.”

The goal by Martins was more than sufficient to take down FC Dallas, a club Seattle has throttled six times in eight matches at the Clink, but Leo Gonzalez added a surprising twist in stoppage time.

Gonzalez, who entered in the 89th minute as a replacement for Andy Rose, took a pass from Neagle directly in front of the net and knocked in his first goal since June 5, 2010, a game winner against the New England Revolution.

The Sounders did not allow FC Dallas a shot on target in the second half and wound up taking nine of their own after only two attempts in the first 45 minutes. Seattle trailed in time of possession in the first half, 51 percent to 49, but ultimately controlled the clock 50.4 to 49.6.

Notes

The Sounders moved one point ahead of D.C. United, which plays at Orlando Sunday, in the Supporters’ Shield race . . . Seattle goalkeeper Stefan Frei made two saves and earned his MLS-leading eighth shutout . . . The Sounders played without Marco Pappa, summoned to Guatamala for national team duty, and Ozzie Alonso, out with a hamstring injury . . . The Sounders, who played to a 0-0 draw with FC Dallas March 28 in Frisco, TX., have won their last five vs. the Texans at the Clink.

Next

The Sounders play the Portland Timbers in U.S. Open Cup competition Tuesday at 7:30 p.m. at the Starfire Sports Complex, then host the San Jose Earthquakes at 1 p.m.  Saturday (JoeTV).