No one needs to remind the San Jose Sharks about the difficulties of closing out a playoff series, how each missed opportunity can give confidence to the opponent and plant seeds of doubt in the leading team.

Two years after becoming the fourth NHL team ever to lose a best-of-seven series after winning the first three games, San Jose is trying to pull off a historic comeback of its own in the Stanley Cup Final.

The Sharks looks to stave off elimination for a second straight contest and force a decisive seventh game in the final when they host the Pittsburgh Penguins in Game 7 on Sunday night.

"The longer it goes, you just feel that pressure, 'You got to get it done, you got to get it done,'" defenseman Justin Braun said. "And when it doesn't happen it creates a little frustration and you're like, 'We could have been done with this days ago and we're still going.' I think that gets in your head a little bit."

That's what happened to San Jose in the first round in 2014 against Los Angeles and what the Sharks hope the Penguins are feeling after failing to win the Cup on home ice in Game 5.

Despite being outplayed for much of the series, including the Game 5 win when Pittsburgh outshot San Jose 46-21, the Sharks know the pressure on the Penguins will only increase of they can win at home to force the winner-take-all seventh game in Pittsburgh on Wednesday night.

"I've been a part of teams, especially over there, that have lost being up 3-1," said Sharks defenseman Paul Martin, who spent the previous five years with Pittsburgh. "I think it's more of a mental thing realizing your opportunity to finish it off is getting smaller and each loss gives that other team that much more belief and momentum that they can get it done and pull it off."

No team has lost the Stanley Cup Final after going up 3-1 since Toronto rallied to beat Detroit in 1942 after losing the first three games of the series.

But the Penguins have had problems closing out their playoff series in recent years. Since winning their third Stanley Cup back in 2009, they have blown series leads three time in the previous six postseasons.

They lost to Montreal in 2010 after going 3-2 in the series and then squandered 3-1 edges in losses to Tampa Bay in 2011 and the New York Rangers in 2014.

Now they lost in their first chance to close out the Sharks.

"I thought our guys did a really good job of handling it the right way," coach Mike Sullivan said. "It was unfortunate that we didn't get the result we were looking for. But we're playing a very good opponent and we know that. We know this is the most difficult win to get. Our players are well aware of the expectations and the heightened intensity that we need to have in order to get this next win."

The Penguins have little they would want to change from their Game 5 loss, other than the start. After allowing two goals in the first three minutes, Pittsburgh dominated much of the rest of the contest.

The Penguins scored twice in a 22-second span to tie the game just a few minutes after their early deficit and controlled the play over the final 58 minutes.

Only a stellar performance by San Jose goalie Martin Jones and a somewhat soft goal that Matt Murray allowed to Melker Karlsson later in the first gave the Sharks the win.

"While we were pretty good, it wasn't enough," forward Matt Cullen said. "You can look at good fortune or bad breaks or whatever. It doesn't matter ultimately. The bottom line is we get a second shot at this and we don't want to miss it."

Murray has done especially well this postseason after any subpar performances. The rookie netminder has not lost back-to-back games all postseason. He followed up a shaky performance in Game 3 by topping 23 of 24 shots on the road in a 3-1 win in Game 4.

Murray is 5-0 with a .935 save percentage in the starts following his first five playoff losses.

"Usually it takes players a few years to acquire that type of mental toughness where your confidence doesn't get shaken or your performance doesn't get influenced by some of the adversity that you go through throughout the course of a game or from game to game," Sullivan said. "Matt has shown an ability to just stay focused and just stay in the moment and be ready to compete and make that next save."