Albert Rusnak scored on a penalty kick in the 11th minute, and goalkeeper Nick Rimando earned his fifth shutout of the season as Real Salt Lake beat FC Dallas 2-0 on Saturday at Rio Tinto Stadium in Sandy, Utah.
The win was the second in four days for Real Salt Lake against teams that were atop the Western Conference when they entered Rio Tinto Stadium.
Rusnak converted from the spot, beating FCD's Jesse Gonzalez low to the goalkeeper's right side. The penalty kick was awarded after Dallas' Kellyn Acosta fouled Sebastian Saucedo in the box in the ninth minute.
Rimando had to record only one save to earn the 142nd clean sheet of his career, which began in 2000 with the defunct Miami Fusion, continued for five seasons beginning in 2002 with D.C. United and with Real Salt Lake since 2007.
Jefferson Savarino kept RSL in front when he headed a shot off the line at the near post in the 71st minute, a dead-on header by FC Dallas' Matt Hedges that seemed destined for the goal.
Real Salt Lake added a crucial insurance goal from Luis Silva one minute into second-half stoppage time. Silva, who entered the game in the 63rd minute, took a perfect pass from Savarino across the goal and beat Gonzalez with his left foot to the goalkeeper's left side.
Real Salt Lake improved to 8-1-1 at home this season.
RSL outshot FC Dallas 14-13, placed six shots on target to just two for the visitors, and owned advantages in total passes (569-360), possession percentage (61 percent-39 percent), and passing accuracy (87 percent-76 percent).
FC Dallas lost to a Western Conference team for the first time this season.
FC Dallas still owns a 19-12 edge all-time in matches against Real Salt Lake, with seven draws. RSL has now won 11 of the 21 matches at home, with four ties.
Next up for Real Salt Lake is a road match at Minnesota United on July 14. FC Dallas heads home to host the Chicago Fire, also on July 14.