Last week, the Nashville Predators did something very few experts thought they had a chance of doing — they swept the mighty Chicago Blackhawks. Chicago has been a perennial Stanley Cup contender for the better part of the last decade, winning three of the NHL’s last seven championships. Along with Scotty Bowman’s Detroit Red Wings, they’re the closest thing to a dynasty the NHL has seen since the days of Wayne Gretzky and the Edmonton Oilers. Sweeping that kind of team in a playoff series is exceptional. Now, as the Preds attempt to beat the St. Louis Blues and reach the conference finals for the first time in franchise history, it’s natural to wonder how much of that exceptional play they can expect to keep up.

A lot of things went right for the Predators in their series against Chicago. Nashville’s offense (never its best asset) took care of business against the Blackhawks, scoring the third-most goals per game of any team in the first round and putting pucks in the net at a better clip than it did during the regular season. Predator centers won the majority of the faceoffs they took against the Blackhawks, and the team as a whole drove possession at the highest rate of any team still alive in the postseason.

But even with all those advantages, it was the otherworldly play of goalie Pekka Rinne that really decided the series. The Blackhawks took 126 shots against Nashville’s defense, and Rinne stopped 123 (or a stunning 97.6 percent) of them. No one can sustain a .976 save percentage over long stretches of games — even the best season-long rates are way lower — but could a goalie play this well over the course of an entire postseason?

A handful of others have come close. In 2006, Cam Ward sprinted out of the gates and posted a save percentage of .940 for the Carolina Hurricanes in the first round of the playoffs. Stiffer competition in the second, third and final rounds of the playoffs meant that Ward’s numbers dipped a bit, though he finished with a save percentage of .920. (The regular-season league average that year was .901.) The Hurricanes won the Stanley Cup, and Ward secured the Conn Smythe trophy as the playoff MVP.

Then there was Corey Crawford’s run for the Blackhawks in 2013. Crawford posted an impressive .950 save percentage in Chicago’s first-round victory over the Minnesota Wild. He, too, regressed in the next three rounds, but he still finished with an overall save percentage of .932 — not bad for a guy whose regular-season mark that year was .926. And like Ward’s Canes, Crawford’s Blackhawks rode their goalie’s remarkable playoff performance all the way to Stanley Cup victory.

These kinds of postseasons don’t always end in championship parades. Chris Osgood got off to a spectacular start for the Red Wings in the spring of 2009. Like the others, he regressed a bit — and like the others, he led his team to the finals. Unlike the others, though, Osgood’s Wings fell one win short of getting their names etched onto Lord Stanley’s shiny silver punch bowl.

So although Rinne has been on fire, it can’t last forever. He’s bound to regress to the mean — but his mean is pretty dang good, too. In 52 career playoff games, he has posted a .917 save percentage and a 2.38 goals-against average. Since the 2004-05 lockout, only 12 other goalies have played in as many playoff games as Rinne, and in that group, his save percentage and goals against average rank seventh and sixth, respectively. Rinne has played a lot of playoff games, and he’s played well.

That hasn’t always been enough, as the Predators are accustomed to making early postseason exits after struggling to put the puck in the net. Including this season, Nashville has made the playoffs six times since Rinne took over as the team’s starting goalie in 2008-09. In those six postseasons, Rinne’s teammates have only averaged 2.6 goals per game in front of him. It’s worth pointing out that, since the lockout, no team that’s averaged less than 2.76 goals per playoff game has gone on to claim the Stanley Cup.

If recent history tells us anything, it’s that the Predators will need to sustain their current scoring pace if they have any hope of advancing past the second round for the first time ever. And if they want a shot at winning the whole thing, it wouldn’t hurt if Rinne could sustain his pace as the postseason’s designated hot goalie. Beating Chicago was a good first step, though, even if there’s plenty of work left for Nashville to do against St. Louis — and beyond.

CORRECTION (April 26, 5:20 p.m.): An earlier version of this story misspelled Pekka Rinne’s name in the photo caption.