Javier Morales and Fabian Espindola stepped up in Alvaro Saborio's absence.
Morales and Espindola both scored in the first half to lead Salt Lake to a 2-1 victory over the Portland Timbers on Saturday night.
''We got big time plays from a couple of big time players there on the attacking end,'' RSL coach Jason Kreis said.
Saborio, second in the MLS with 14 goals, missed the game due a shoulder injury suffered against Tauro FC earlier in the week. He is expected to be sidelined at least two to four weeks.
Real Salt Lake (15-11-4) became the second club in MLS history to get at least 15 wins in three straight seasons and secured a spot in the playoffs for the fifth straight year.
Bright Dike scored in the 61st minute for the Timbers (7-15-8), who remained winless on the road. Portland only has two more chances - with games remaining against Seattle and Vancouver - to end the futility.
''The reality of it is we don't want to be one of those teams that goes down in the record book without a win on the road during the course of a year,'' Portland midfielder Jack Jewsbury said.
Espindola put Salt Lake on the board in the 14th minute, taking a free kick just outside the penalty area and slicing a left footer past the Timbers' defensive wall.
Salt Lake goalkeeper Nick Rimando prevented Portland from tying it up in the 21st as Jewsbury used a corner kick to send a perfect cross to Rodney Wallace in the center of the box. Wallace sent a header forward and Rimando denied him in the center of the goal.
Morales made it 2-0 in the 36th on another free kick as he fired the ball over the wall and out of reach of the outstretched hand of Timbers goalkeeper Joe Bendik.
''We just got more numbers involved tonight,'' Kreis said. ''There was more options for players, when they were on the ball, to find passes. We created a lot of very good chances just passing and moving and being dynamic in the attacking third of the field.''
Rimando prevented a potential tying goal off a free kick in the 81st minute as he leaped up to swat away a ball sent in by Franck Songo'o.
Salt Lake suffered from a letdown in energy on defense during the second half and Rimando felt like the team didn't do enough to put the game out of reach when it had a chance.
''We could have scored five or six goals tonight,'' Rimando said. ''We got to put our opportunities away, especially at home and especially against teams that are fighting for their jobs. It's only going to get harder and if we don't put our chances away, other teams will.''