The Galaxy twice came from behind to grab a share of the points when it seemed the Quakes would take the maximum home with them.
Bobby Convey hit the target for San Jose in just the 2nd minute before Edson Buddle grabbed his 12th goal of the season just before the hour-mark to make it 1-1.
Brandon McDonald made it 2-1 to the visitors with just over twenty minutes remaining and it looked like a Quakes win until LA got another equaliser in the 90th minute through Donovan who was on hand to tap home after San Jose keeper Jon Busch could only knock a long range Tristan Bowen shot into the path of the USA star. Donovan finished with the easiest of knock ins to notch up his 99th career MLS goal.
"It was a poor star from us. We've got to do better at the beginning of games, you can't do that," Donovan told ESPN immediately after the match.
"I was proud of the way we responded. I'm still trying to figure out how we didn't win, we had so many chances, but sometimes it happens like that.
"We said at half-time it was a good test for us because in most games we've been ahead so I was proud of the way we responded, we kept going. I thought played actually really well except for the two mistakes. Another night we probably win but we're happy with that."