A first-half penalty kick from Alvaro Saborio was enough to give Real Salt Lake all three points against Houston Dynamo on Saturday.
The Costa Rican international did the honours from the spot after Adam Moffat had brought down Olmes Garcia in the 36th minute at Rio Tinto Stadium.
Houston, who were unbeaten in their previous four games, came close to finding an equaliser in the second half, but Nick Rimando produced a super save to keep out Jason Johnson's goal-bound header.
The win moves Real four points clear at the top of the MLS Western Conference.