Rooney completed his hat-trick in the 65th minute and moments later Real Salt Lake lost another man when Marcelo Silva received a second yellow for a foul on Lucas Rodriguez.

Rodriguez and Ulises Segura added the insurance in the 76th and 80th minute respectively, giving United seven points from their first three matches.

The Los Angeles Galaxy were still without the injured Zlatan Ibrahimovic but edged past Minnesota United 3-2.

LA built a 2-0 lead after Jonathan Dos Santos converted a spot kick and Chris Pontius found the net in the 41st minute before Jan Gregus pulled one back for Minnesota 15 minutes from time.

The Galaxy restored the two-goal advantage when Sebastian Lletget scored his first of the season with nine minutes remaining and substitute Angelo Rodriguez ensured a tense finish when he found the net in the 87th minute but Galaxy held out for the win.

The Seattle Sounders maintained their winning ways with a 4-2 victory over Chicago Fire.

Victory looked inevitable when Seattle led 3-0 49 minutes into the game, but Raheem Edwards and Fabian Herbers pulled two back for Chicago to put the visitors under pressure.

A late strike from Raul Ruidaz ensured the victory and earned his side their third win in a row.

In the night's other games, Alex Muyl bagged a brace in the New York Red Bulls' 4-1 thumping of the San Jose Earthquakes, and Memo Rodriguez was on target twice to lead the Houston Dynamo 3-2 over the Vancouver Whitecaps.

Ignacio Piatti also scored twice in the Montreal Impact's 3-1 win against Orlando City, and Gaston Sauro was the lone scorer in the Columbus Crew's 1-0 home win against FC Dallas.

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