SAN JOSE — About the only thing Patrick Marleau is struggling at so far this season is finding an explanation for his record start.

Marleau became the second player in NHL history to open a season with four straight multigoal games, striking twice on the power play in the first period in the San Jose Sharks’ 4-0 victory against the Colorado Avalanche on Saturday.

“I’ll keep taking them if they keep coming,” he said. “That’s for sure.”

Marleau has scored exactly two goals in each game this season, joining Ottawa’s Cy Denneny in 1917-18 as the only players to open a campaign with four multigoal games, according to the Elias Sports Bureau.

“He obviously has a hot hand right now,” defenseman Brad Stuart said. “We’ll need contributions from everyone at some point. But right now Patty is playing amazing and putting the puck in the net every time he touches it it seems like.”

Both of Marleau’s goals came after Ryan O’Byrne took two additional minor penalties for retaliating after Stuart flattened Colorado captain Gabriel Landeskog with a vicious hit.

Joe Thornton added a power-play goal in the second period, giving San Jose 10 power-play goals in four games and a franchise record 19 overall.

Thomas Greiss made 24 saves for his first career shutout and Matt Irwin got his first career goal as the Sharks are off to their best start since also winning the first four games in 2008-09.

The Avalanche lost their seventh straight game in San Jose since winning Game 1 of their first-round playoff series in 2010. After killing off 16 straight penalties coming into this game, Colorado allowed goals on San Jose’s first three power plays, including two after the hit on Landeskog.

“You have a situation where a teammate is defending another teammate which is the game of hockey and in those situations we need to step up and get the job done for our teammate,” Colorado coach Joe Sacco said. “We just didn’t get it done. That was the difference in the game.”

San Jose’s power play is in midseason form in this lockout-shortened season, with 10 goals in 24 chances. Marleau has four of those goals as he is off to a scintillating start. He is the first Sharks player ever with four straight multigoal games and has outscored the Sharks’ opponents, who have seven goals in four games.

“I don’t know if he can keep scoring two goals every night. But he can keep his play up the way it’s been,” coach Todd McLellan said. “He’s been skating extremely well. A ton of confidence. He’s prepared to shoot the puck. He’s engaged physically. It’s a great reward for him. He came focused to play.”

The Sharks took more than 12 minutes to get their first shot on goal, but managed to take a 2-0 lead in the first period because of stellar special teams play and a big hit by Stuart that changed the complexion of the game.

San Jose’s troubled penalty-kill unit was up to the task early, allowing no shots on two power plays for Colorado. Then San Jose’s dangerous power-play took over late in the period after Stuart’s big hit that Landeskog felt was clean even if his coach thought it should have been a penalty.

“It was hard, that much I could tell you,” he said. “I was reaching for the puck and didn’t brace myself enough, Stuart stepped up and that’s the way hockey always is. It was a big one. I knew he was there but I didn’t think he was coming at me. Then he came and I saw him at the last second but not nearly early enough.”

O’Byrne took offense and challenged Stuart to a fight. The Sharks came out of the scrum with two power plays after O’Byrne got hit with an instigator penalty and one for fighting with a facemask. Landeskog left the game briefly before returning for the second period.

Marleau and the Sharks made Colorado pay. Just 28 seconds into the first power play, Marleau whacked at a rebound and knocked it past Semyon Varlamov to give San Jose the lead.

He delivered again on the second power play after a nifty passing display from Dan Boyle to Thornton to Marleau, who tapped the puck in by the side of the net for his fourth straight two-goal game.

“We weren’t playing particularly well. Then you get those two power plays and boom, boom, it’s 2-0,” Thornton said. “Really it was a huge momentum switch for us.”

NOTES: Marleau is the first NHL player with fourth consecutive multigoal games since Alexander Mogilny had five straight in 1992-93 for Buffalo. … Recently signed Scott Gomez made his Sharks debut on the fourth line in place of James Sheppard and also got time on the second power-play unit. … O’Byrne got 19 minutes of penalties for his scuffle with Stuart as both players were sent off for fighting and O’Byrne got an additional 10-minute misconduct.