Robbie Keane got his fifth goal in the last four games to help the Galaxy (9-10-3) win for the sixth time in nine games since returning from a three-week break in June. Donovan has seven goals and Keane six in that span.
Donovan and Keane led the way for the explosive Galaxy, who took 12 of the 15 shots in the second half.
“Those two combined for a number of opportunities tonight and were outstanding,” Galaxy coach Bruce Arena said. “We’ve been scoring an awful lot of goals, and it’s been pretty damn good.”
Paolo Cardozo scored his first MLS goal in the 52nd minute for Chivas (6-8-5), which lost for the second time in 10 league matches.
Keane scored from David Beckham’s through ball in the 14th minute to put Los Angeles up 1-0.
Donovan, who has nine goals this season, scored on Keane’s through ball in the 48th to double the lead, and got his second on a goalmouth scramble following a corner kick in the 78th.
“They’re a good enough team that they don’t need any help,” Chivas coach Robin Fraser said. “I certainly feel like a lot of their opportunities came off our turnovers or not being clean enough with the ball. Obviously, they have some very good attacking players, and if you give them the opportunity to be dangerous, they’re going to be dangerous.”
Beckham’s three-game goal-scoring streak ended, but he had assists on the first two goals.
Keane, who also has nine goals, nearly had his third two-goal game in three weeks. He also scored in the 20th minute on a near mirror of his first goal, taking a through ball from Donovan, dribbling past Kennedy and firing into the open net, but was flagged offside, a call that replays put into doubt.
The Galaxy have 22 goals in their last seven games after scoring just 16 in the first 15 matches.
“We’re playing well. Our guys we depend on to make plays are making plays,” said Donovan, who also hit posts in the 62nd and 76th minutes. “And, candidly, we’re probably leaving a few goals on the table each game. As good as we feel like this is, we know we can be better.”
Omar Gonzalez made his first appearance since returning from torn knee ligaments in the Galaxy’s July 4 loss to Philadelphia. The 6-foot-5 center back, last year’s MLS defender of the year, was a 68th-minute substitute for Jimenez.