SAN JOSE -- The Sharks have a goalie decision to make. It shouldn't be a tough one.

Alex Stalock, come on down.

There was no official word Sunday that Stalock will indeed be replacing Antti Niemi in net for Monday night's Game 6 against the Los Angeles Kings. But anyone with two eyes who has watched Niemi struggle in the last two games would surely reach that conclusion.

Todd McLellan has two eyes.

"We've got to think about that and decide," the Sharks coach said Sunday, insisting he hasn't yet made up his mind.

The Sharks practiced for about 30 minutes before flying south. You had to figure McLellan would tell the two goalies of his decision somewhere over Paso Robles. If he hadn't done so already.

On the surface, it might seem like a gutsy move to replace Niemi, who won a Stanley Cup as the Chicago Blackhawks' goalie in 2010 and has 59 more games of NHL playoff experience than Stalock. But after Niemi was pulled out of the past two games against the Kings for uneven performance ... well, there's only one next logical step.

Consider: Of the goalies still donning masks in the playoffs, Niemi has the worst save percentage (.882), falling even lower than the Kings' Jonathan Quick (.893), who began the series by allowing 12 goals in the first two games.

Meanwhile, even though the 26-year-old Stalock has never started an NHL playoff game, he has stopped all 26 shots he's seen in his two relief appearances. In Game 4, one puck did get past Stalock -- but the goal was disallowed because of an L.A. penalty committed in front of him before the shot.

The biggest mistake for the Sharks, however, would be if the other players see the change to Stalock and figure their problems of the past two games have been solved. That's far from the truth.

McLellan and his staff watched video of Saturday's egg-laying performance by the Sharks in their 3-0 loss. And as an old football coach once said the video looked suspiciously like the game itself. The Sharks were sloppy and slow and just not very good through long stretches.

"At the end of the day, we weren't good enough," said Joe Pavelski, declining to dissect it much further.

Dan Boyle, the defenseman, pointed out a few more specific elements that caused the ugliness -- passing that wasn't crisp, playing too much in the Kings' end of the ice, etc. -- but sometimes the most basic numbers on the stat sheet tell the most important story.

Such as? Saturday, the Sharks' best shooters were hardly shooters at all. And that can't continue. In the series' first four games, nine of the Sharks' goals were scored by Pavelski, Patrick Marleau, Tomas Hertl and Matt Nieto. But in Game 5, that foursome was credited with just three total shots.

Most alarming: Marleau, the Sharks' leading scorer in the series, didn't put a single puck on net. The stat sheet credited him with five "missed" shots. Marleau is one of the most accurate snipers on the team. So either the Kings were forcing him to take aim from spots he doesn't favor, or they were crowding him as he took the shots to throw off his timing. Or his release was lousy. Or he simply had a bad game.

Some of the problem may have been all the time and energy spent by Marleau's line -- with Nieto and Logan Couture -- trying to play defense against the Kings' Anze Kopitar line. That matchup was won by the Kopitar line all evening. And the Marleau-Couture-Nieto line wasn't the only Sharks line that spent too much time playing defense instead of offense.

"We'd like to get ahead of the curve instead of chasing it," McLellan said.

Should the Sharks still be favored to win the series, given their 3-2 lead? Of course. But they need to clean up their slapdash errors of the past two games.

Remember, odds remain heavily in their favor. In the history of NHL playoffs, there have been 175 series that started out 3-0. Only three of those teams that built a 3-0 lead have blown it by losing four straight -- the 1942 Detroit Red Wings (to Toronto), the 1975 Pittsburgh Penguins (to the New York Islanders) and the 2010 Boston Bruins (to the Philadelphia Flyers). Five other teams have started a series 3-0 and was extended to a seventh game before clinching, including the Sharks in 2011 against Detroit.

"We like where we're at," McLellan said, taking the optimistic approach. "We're still in the driver's seat."

It's just time for a new goalie back there in the rear.

Read Mark Purdy's blog at blogs.mercurynews.com/purdy. Contact him at mpurdy@mercurynews.com.