Chicago Fire moved into third place in the Eastern Conference with a 3-1 win over Houston Dynamo.
Patrick Nyarko opened the scoring in the first minute and Daniel Paladini made it 2-0 with just 19 minutes on the clock.
Dynamo substitute Brian Ching pulled a goal back in the 90th minute, but Brazilian Alex made certain of the win in injury-time with a long-range shot which went in off the post.
In the Western Conference, Seattle Sounders moved a point clear of Los Angeles Galaxy in third place with a 1-1 draw at FC Dallas.
Mauro Rosales opened the scoring for Seattle on 20 minutes, but Brazilian Jackson equalised 12 minutes later.
San Jose remains well clear of the chasing pack after a 4-0 win over Chivas USA.
Victor Bernardez (11) and Simon Dawkins (39) put the Earthquakes in command and a late double from Ramiro Corrales completed the rout.