Ben Lovejoy's slap shot from inside the blue line beat Antti Niemi 2:48 into overtime to give the Ducks a victory at SAP Center.
Corey Perry's goal at 16:01 of the second period had tied the game after Tyler Kennedy scored shorthanded at 8:15 to put the Sharks ahead 2-1. San Jose rookie Thomas Hertl opened the scoring at 14:42 of the opening period. Anaheim's Emerson Etem tied the game by beating Niemi 2:48 into the second.
"He can skate a hundred miles an hour and he's a big, strong man," coach Bruce Boudreau said of Etem. "His improvement from day one last year tto the first time he got called up, to when he got sent down, to the second time he got called up, to through the playoffs and then until now-- you can see improvement in him every day."
Etem didn't play the third period after suffering a lower-body injury in a collision with San Jose's Raffi Torres.
The Sharks are still getting their legs under them. They host the Phoenix Coyotes on Saturday.
"It was what it was. It was a preseason game," Sharks defenseman Dan Boyle said. "I think there was definitely a lot of rust out there for a lot of guys. Some guys were a little better than that. Both the two new guys, Hertl and Kennedy, had some pretty good shifts out there. It was a little rusty, but we'll work and get better."