The Los Angeles Galaxy remain three points clear of FC Dallas at the top of the Western Conference after both sides enjoyed home wins on Saturday.
The Galaxy fell behind to Sporting Kansas City when Omar Gonzalez scored an own goal in the 39th minute, but Landon Donovan levelled from the penalty spot just before half-time.
Donovan struck again just a minute into the second period and Juan Pablo Angel and David Beckham also got on the scoresheet with a superb free-kick to secure a 4-1 win.
FC Dallas beat Philadelphia Union 2-0 with Brek Shea (29) and Fabian Castillo (43) scoring their goals.
Elsewhere, DC United and Colorado Rapids drew 1-1, with Drew Moor's 23rd-minute goal for Colorado cancelled out by a 61st-minute penalty from Chris Pontius.
Another penalty settled matters between the New England Revolution and Vancouver Whitecaps, Shalrie Joseph scoring from the spot in the 49th minute to give New England the 1-0 win.
Goals from Chris Wondolowski, Steven Lenhart and Khari Stephenson in a 12-minute spell in the second half ensured the points were secured by San Jose before Brandon McDonald was sent off 11 minutes from time.
The Seattle Sounders and Portland Timbers had to settle for a point apiece in a 1-1 draw after Alvaro Fernandez's goal for Seattle was cancelled out by Mamadou Danso, while Toronto FC and Chicago Fire played out a 2-2 draw.
Joao Plata and Maicon Correa looked to have set Toronto on their way to the win, but Marco Pappa (63) and substitute Orr Barouch (75) replied for the visitors.