68 Percent! NHL Regular-Season Series Matter in the Playoffs

68 Percent! NHL Regular-Season Series Matter in the Playoffs article feature image

John E. Sokolowski-USA TODAY Sports

The Stanley Cup Playoffs, which start Wednesday, are notoriously difficult to predict. One of the things we like about them, as sports fans, is that so many of the series come down to the wire, whether it’s a couple overtime games along the way, or a Game 7. There is constant drama and unpredictability. In hockey, more so than any other sport, it is often thought that as long as a team can make it into the postseason, it has a chance to win it all. This can also make betting on series particularly difficult. What factors are important to consider?

It seems like every year results come at us that we didn’t expect, and underdog prices hit at a seemingly random clip.  This year, teams like New Jersey, Colorado and Philadelphia will try to win as underdogs of 2-1 or greater. I think one of them has a great chance to do so.  But we’ll get back to that later.


To illustrate the difficult-to-predict argument of the Stanley Cup playoffs, consider this: The team with home ice in the first round is the team with the better record, and is always installed as a favorite of some kind (sometimes a particularly small favorite, but always a favorite). That team — that favored, home-ice, better-record team — has won just 59.4% of the series in the past 4 years. The NHL changed its playoff format completely four years ago, and for the purposes of this piece, we are just using data from that time. Less than six out of 10, for teams with a better record and home ice. Compare that to the NBA, where over the same period of time 78.1% of the teams (25 out of 32) with home-court, better seed and better record won in the first round. Even crazier is that all but one of the seven losses was in the 4 vs. 5 match-up, where there should be more upsets because the teams are closest in record.

So if the factors we would traditionally consider significant for a the first round don’t apply to hockey in the same way, what does? The regular season may not matter overall, but the regular-season series between first-round opponents matters quite a bit.

I said before that if you just picked home teams in the first round, you’d be right 59.4% of the time. Well, if you picked the team that won the season series, you’d be right 68% of the time (17 out of 25 applicable series — no regular-season series ties allowed), the past four seasons.

And that is surprising, on a number of levels. First, a bit of explaining.

I calculated the season series winner in all cases by including overtime wins/losses but excluding any game that went to a shootout. Shootouts don’t exist in the Stanley Cup Playoffs so those results are particularly irrelevant.  Although the league went to 3-on-3 overtime the past couple seasons as well, this is, at least on some level, still hockey, and I thought it still mattered.  So when you see a season series and it doesn’t match with what you see somewhere else, that’s probably why.


Anyway, 68 percent. 68 percent! A factor much more predictable than home ice or the Vegas favorite (which are the same in this case). And the truly wild part about that number is that it brings lots of much larger prices into play, since teams may drop a season series to a team much worse than they are for a variety of reasons.

Now, I understand that this percentage has some pitfalls. Teams in the regular season obviously don’t play the same goalie every game, and have injuries, and are on back-to-backs, all factors which can affect performance on any given night. But, it seems like a mistake to outright ignore this data because of those  potential variables. Maybe there is something to the idea that a particular matchup is very beneficial for one team, so much so that it can overcome a difference in talent over seven games?

For this season, since I know you’re curious, using my methods (which ignore shootouts but not overtimes), seven of the eight first-round series feature a regular-season winner (Vegas vs. LA was a wash). They are:

Devils (currently +260) over Lightning
Maple Leafs (+125) over Bruins
Capitals (-130) over Blue Jackets
Penguins (-240) over Flyers
Predators (-525) over Avalanche
Jets (-220) over Wild
Sharks (+100) over Ducks

Four years of history would tell us that about 4-5 of those teams are going to win their first round series. Now, I don’t think blindly betting every single regular-season series winner is necessarily the best approach, just like blindly betting anything isn’t the best approach. But it’s one more thing I’ll be considering before placing my first-round bets.

Top photo: Toronto’s Auston Matthews