There have been only four different Stanley Cup winners in the past nine seasons, with the back-to-back defending champion Pittsburgh Penguins and the Chicago Blackhawks leading the way with three titles apiece. The Los Angeles Kings have two and there's one for the Boston Bruins.

Can a fifth team break into the winner's circle in 2017-18? The clubs knocking on the championship door include the Anaheim Ducks and Washington Capitals, along with a number of Canadian clubs.

Here's a primer for the upcoming NHL season, which opens its doors tonight with four games, including Toronto at Winnipeg, and Calgary at Edmonton.

Will Canada's Stanley Cup drought end this year?1:37

5 storylines to watch

Canadian content

June 9 will mark the 25th anniversary of Patrick Roy and the Montreal Canadiens upending Wayne Gretzky and Los Angeles in the 1992-93 Stanley Cup final. Can a Canadian-based club break through this season and end the championship drought?

There certainly is plenty of optimism. In Edmonton, the Oilers have a wonderful one-two punch with Connor McDavid and Leon Draisaitl. In Calgary, the Flames have a newcomer in goal in Mike Smith, an excellent blue-line and have added the ageless Jaromir Jagr.

The Ottawa Senators are coming off a trip to the East final, though their top player, Erik Karlsson, could miss the start of the season as he works his way back from off-season foot surgery. The Canadiens have a new young francophone star in Jonathan Drouin and a full season of head coach Claude Julien after his return late last season. The Toronto Maple Leafs have added Patrick Marleau to their young Auston Matthews-led group. The Winnipeg Jets also have magnificent young players in Mark Scheifele and Patrik Laine.

Even the rebuilding Vancouver Canucks are worth checking in on, with rookie head coach Travis Green leading a team that must decide what to do with the 37-year-old Sedin twins, Daniel and Henrik.

5 things about the 2017-18 NHL Season​1:40

The young lions

The NHL has become a young man's game. Last year, McDavid became the third-youngest player (behind Sidney Crosby and Gretzky) to win the Art Ross Trophy. In the summer, the 20-year-old Oilers captain signed an eight-year extension worth $12.5 million US a season, making him the highest-paid player when the contract kicks in next season. There was no sophomore jinx for McDavid.

There also was quite an impression made by last year's rookie class of Matthews, Laine, Columbus Blue Jackets defenceman Zach Werenski and Penguins goalie Matt Murray, who won his second Stanley Cup with Pittsburgh last spring. Will there be any sophomore slumps among this group? How will the top two picks in last summer's draft — forwards Nolan Patrick (Philadelphia Flyers) and Nico Hischier (New Jersey Devils) — perform in their first campaigns? They certainly have a tough act to follow.

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After a stellar rookie season, Auston Matthews appears to have the tools to avoid the dreaded sophomore slump. (Jeffrey T. Barnes/Associated Press/File)

NHL-less Olympics

It sure would be nice to have watched McDavid, Matthews and Laine clash with the game's best in South Korea this February. But NHL commissioner Gary Bettman has taken the Olympic spectacle away from them and the likes of Canada's Crosby, Sweden's Karlsson, Russia's Alex Ovechkin, American Jack Eichel and others.

But that doesn't mean the Olympic men's hockey tournament won't be interesting. It will still be closely followed in Canada and Europe, and what if the United States breaks through for a gold medal?

After five years of the game's best in the Olympics, it will be interesting to see the interest level among hockey fans in this country as we get closer to Pyeongchang.

John Tavares's pending free agency

The 27-year-old New York Islanders captain could be the most eligible unrestricted free agent on July 1. He has maintained that he would like to remain with the Islanders, but his season begins on Friday and he also has stated that he will not talk contract extension during the season.

Steven Stamkos's return

The Tampa Bay Lightning captain has missed significant time in three of the last four seasons with a broken leg, a blood clot in his shoulder and a right-knee ailment last season. The 27-year-old Stamkos had a solid training camp, but now all eyes will be watching to see what kind of a season the one-time 60-goal scorer can cobble together.

Honourable mentions

The Penguins' attempt at a three-peat; the rule alterations with respect to faceoffs, offside video challenges and slashing; the expansion team in Las Vegas; and Ken Hitchcock's return to Dallas will also be interesting to follow this season.

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New York star John Tavares may not be spending much time with the Islanders this season. (Chris O'Meara/Associated Press/File)

Quick predictions

Top six Cup contenders:

  • Chicago
  • Pittsburgh
  • Washington
  • Calgary
  • Nashville
  • Anaheim

Teams on the rise:

  • Calgary
  • Edmonton
  • Toronto

Teams on the decline:

  • Vancouver
  • San Jose
  • Detroit

Playoff teams — East:

  • Pittsburgh
  • Tampa Bay
  • Washington
  • Toronto
  • Montreal
  • Columbus
  • N.Y. Rangers
  • Ottawa

Playoff teams — West:

  • Chicago
  • Edmonton
  • Anaheim
  • Nashville
  • Calgary
  • Winnipeg
  • Minnesota
  • Los Angeles

Canadian team point totals:

  • Ottawa: 101
  • Toronto: 99
  • Edmonton: 99
  • Calgary: 96
  • Montreal: 95
  • Winnipeg: 90
  • Vancouver: 78

Top 5 hockey pool players:

  • Connor McDavid, Edmonton
  • Sidney Crosby, Pittsburgh
  • Leon Draisaitl, Edmonton
  • Patrick Kane, Chicago
  • Nikita Kucherov, Tampa Bay