The temperature of some NHL rivalries can rise and fall when one rival racks up a string of wins year after year over the other.
Other NHL rivalries remain razor-hot regardless of the standings, and that's the case with the Battle of Pennsylvania between the Pittsburgh Penguins and Philadelphia Flyers.
Both clubs were part of the NHL's 1967 expansion, and have been geographic rivals since. The intensity ratcheted up in the salary cap era, as the two teams met four times in the Stanley Cup playoffs from 2008 to 2018, and again in the first round of the 2026 postseason. Overall, the Flyers hold a 5-3 playoff series edge over the Pens.
The two teams meet for their season-opening matchup Wednesday, the highlight of a three-game slate on the NHL schedule:
Pittsburgh Penguins at Philadelphia Flyers
7:30 ET (TNT) | PHI -142, O/U: 5.5
In addition to all of the history between the franchises, both have a player that made Rachel Kryshak's preseason Calder Trophy watch list. Philly's Porter Martone exploded onto the scene this past postseason, and looks like a cornerstone component of their top six for years to come. Meanwhile, Pittsburgh has possibly the best young goaltender in hockey on the roster in Sergei Murashov, who finished with a .919 save percentage in 38 starts for AHL Wilkes-Barre/Scranton last season.
New York Islanders at Toronto Maple Leafs
7:30 ET (ESPN+) | TOR -120, O/U: 5.5
This game includes a showdown between the past two No. 1 picks: Matthew Schaefer, who won the Calder Trophy as the league's top rookie last season for the Isles, and Gavin McKenna, who joins fellow top picks Auston Matthews and John Tavares on the Maple Leafs.
Los Angeles Kings at Colorado Avalanche
10 ET (TNT) | COL -192, O/U: 6.5
Wednesday's nightcap is another playoff rematch, with the Kings looking to exact some revenge after the Avalanche swept them out of the postseason this past spring. This is Game 1 of the post-Anze Kopitar era for L.A., as the future Hall of Famer concluded his career last season.
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Here's what you need to know:
Greg Wyshynski predicts the future for all 32 teams with his full standings predictions.
Emily Kaplan runs down all the big storylines across the NHL for opening week.
The ESPN family of reporters, analysts and broadcasters made their picks for division winners, the Stanley Cup and all the major awards.
Ryan S. Clark and Kristen Shilton went deep with all the intel you need on all 32 teams.
Wild defenseman Brock Faber had surgery on his fractured skull, with his return TBD.
The Maple Leafs and Blue Jackets swapped Kirill Marchenko for Matthew Knies (with four other players involved).
The Hurricanes and the Avalanche are co-favorites to win the Cup, according to the sportsbooks.
Tuesday's scoreboard
Florida Panthers 1, Carolina Hurricanes 0 (OT)
Montreal Canadiens 3, Toronto Maple Leafs 2
Boston Bruins 3, New York Rangers 0
Vancouver Canucks 6, Edmonton Oilers 5 (OT)
Vegas Golden Knights 5, Chicago Blackhawks 2
NHL scoring leaders
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NHL goaltending leaders
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Today in hockey history
On this day in 1997, the Maple Leafs named Mats Sundin their captain, the first European-born player to be an NHL captain. He would wear the "C" for 11 seasons for Toronto.
Sundin returned to the Leafs franchise this year, taking on the role of senior executive adviser, hockey operations.