Goaltenders are known as "the great equalizers" in the Stanley Cup Playoffs. They give every underdog a chance at an upset. They give every favorite the cold sweats, knowing one bad round from their goalie could be their ultimate undoing.

As the 2021 Stanley Cup Playoffs arrive, which teams are in the best and worst positions with their goaltending?

Former NHL goalie Stephen Valiquette, CEO of Clear Sight Analytics and one of the sport's foremost analysts on netminders, believes that goalies who let in a high percentage of low-danger goals during the season are the ones that have struggled in the postseason.

"What I look at the most entering the playoffs every season is: Which goalies are allowing the most low-danger goals? Now, the difficult thing about this for the general public is that in hockey, no one knows what a low-danger goal is. If a player walks into the slot, has a clear view at the goalie, tries to beat him clean, we might say that's a great save. But guess what? He's supposed to make that save, because everyone else does. And sometimes when the goalie get scored on, we'll say a player had lots of time and space and other excuses, but it's not like that: Every other goalie in the league stops that shot, and so should you," said Valiquette.

The formula for a top goalie, according to Valiquette: They perform at league average on high-danger chances; they stop all the mid-danger shots; and only the worst allow too many low-danger goals. "That measures clutch. The goalies that are measured by the goals they allow, rather than the saves that they make," he said.

"Low-danger goals are the difference-maker in the playoffs. When a goalie allows one, and the opposing goalie does not, his team loses 86% of the time. You just don't win when your goalie lets one in," said Valiquette.

The ESPN hockey staff and punditry -- along with some outside experts -- ranked all 16 teams based on the quality of their goaltending, from effectiveness to depth to the potential to win a series on their own. Valiquette wasn't part of that ranking, but offered some valuable insight into what he sees from the Stanley Cup contenders this postseason. All stats via Evolving Hockey and Hockey Reference.

Here are the 2021 Stanley Cup Playoff goalie confidence rankings, starting with a winning hand in Vegas: