Donovan scored career MLS goals 133 and 134, as the Galaxy crushed the Goats, scoring four before halftime.
The Galaxy got themselves in front within the game's first six minutes. Gyasi Zardes fired in a low cross from the left which Donovan controlled at the back post and played back for Robbie Keane, who was left with a simple finish from six yards out.
The lead was doubled less than 20 minutes later and again, it was Zardes on the left flank putting in a perfect low cross. This time it was Donovan who was left with an easy tap-in after the cross eluded Dan Kennedy.
And three minutes later, Zardes got on the scoreboard himself when a shot deflected to him inside the box, and the rookie fired home low and to the near post to make it 3-0.
Donovan grabbed his second before halftime and it was a beauty. The forward was played in behind the Chivas USA defense and clipped a shot over Kennedy from outside the box. The goal was the 134th of his career, tying Jeff Cunningham for the all-time MLS regular-season goalscoring record.
In the game's dying moments, Keane grabbed his second and his team's fifth with a chest down and volley to the far post.