Alonso's absence would make life difficult for the Galaxy midfield but Donovan is adamant he wants the four-time club MVP to be present this weekend.
"Ozzie makes them a very good team," Donovan said.
"He is unquestionably their engine, and he's really their leader. When you take him off the field, they're affected pretty severely, we know that.
"We hope he plays," Donovan added. "We know he hasn't trained all week, so it's looking less and less likely that he will play, but we're going to prepare as if he's playing, and we want him to play.
"If we're going to win, we want to beat the best team."
For breaking stories and all the great banter like us on Facebook: facebook.com/tribalfootball