Galaxy face Sporting Kansas City this weekend.
"David is very [important] to what we're trying to do here, obviously, with free kicks and the assists he produces every year," Keane said. "It's up to the players now who when David's out to take responsibility and take the chance and make the most of it.
"I try to take free kicks as much as I can," he said, "but when David's there, he's the man for free kicks. If David's not there, then it's up to someone else to take the responsibility. I'm very happy to do that."