The Ducks drew an unusual delay of game penalty at the start of the second period when they arrived late to the ice from the locker room and weren't prepared to start the period.
Andrew Murray's power-play goal at 18:15 of the third period made the score 5-1.
Mitchell's goal came on a power play at 17:25 of the second period, giving San Jose a 4-1 lead.
Anaheim made it 3-1 when Getzlaf scored 10 seconds into a power play at 14:56 of the second.
Douglas Murray made it 3-0 at 8:24 of the second when he took advantage of Joe Thornton's screen of Ellis.
San Jose jumped out to a 2-0 lead late in the first period when Irwin and Boyle scored.
Irwin's score came on a power play at 15:21. The rookie defenseman was playing in his first NHL preseason game.
Boyle took a pass from Thornton and was quick to get set up and score with 1.4 seconds left in the period.
Sharks goalie Antti Niemi has yet to skate with the team after having a cyst removed last week. ... Last season's backup goalie, Antero Niittymaki, will be out 12 weeks after undergoing hip surgery earlier in the week.
Copyright by STATS LLC and The Associated Press
Arena: SAP Center Location: San Jose, California
Referees: Dan O'Halloran, David Banfield Linesmen: Brian Murphy, Don Henderson
Attendance: 16,541 (94.5% full)
Team Stat Comparison
Power Play Goals
Power Play Opportunities
Shots on Goal
Matt Irwin (1)
(Power Play) Assists: Mike Moore, Michal Handzus
Dan Boyle (1)
Assists: Joe Thornton, Joe Pavelski
Douglas Murray (1)
Assists: Mike Moore, Joe Pavelski
Ryan Getzlaf (1)
(Power Play) Assists: Cam Fowler, Bryan Rodney
Torrey Mitchell (1)
(Power Play) Assists: Michal Handzus, Brent Burns