There is no fancy name for when the New York Islanders face the Philadelphia Flyers. It's not a battle of the boroughs or a cross-river rivalry, but when teams are a bus ride apart they play enough to build up some memories.

A flight is usually required when the Boston Bruins and Tampa Bay Lightning face off, or meetings between the Colorado Avalanche and Dallas Stars, and the Vegas Golden Knights and Vancouver Canucks. Even though the NHL abandoned its divisional playoff format for one year amid special circumstances, all four second-round matchups pit division rivals against each other with a spot in the conference finals at stake.

“There is that kind of close, across-town feel,” Islanders defenseman Scott Mayfield said.

These teams are across the hotel from each other in the Eastern Conference's Toronto and Western Conference's Edmonton bubble, though the familiarity of these foes predates hockey's return. They all have history dating to the regular season and some in previous playoffs, plus Boston-Tampa Bay and Colorado-Dallas are rematches from the seeding round.

The Bruins and Lightning fought it out in a one-goal game Aug. 5 and have been the class of the Atlantic Division for years now. The core groups are largely the same from their 2018 postseason meeting.

“We know each other,” Lightning coach Jon Cooper said. “I think rivalries, they come organically. You never know who you’re going to have one with. But I believe when you play teams in playoffs in recent years, that seems to play into it. We played them a couple years ago, and then we’ve had some pretty intense games with them since. Usually, they’re one-goal games and usually there’s some sort of fireworks that have happened.”

Colorado and Dallas got about 36 hours notice before starting their series Saturday night, a quick turnaround made easier by their recent history. The Avalanche shut out the Stars in round-robin play less than three weeks ago after facing off four times in the regular season.

“It helps with your preparation because there’s not really any surprises coming at you," Avalanche coach Jared Bednar said. “You know the team well, and you’re pretty confident what we’re going to see.”

The Flyers and Islanders know what they'll see in each other beginning Monday, even though the organizations haven't met in the playoffs since 1987, 11 years before Philadelphia goaltender Carter Hart was born. But they played three times this season — all won by New York — and plenty of scouting has happened since.

“I think (the Islanders have) played as well as any team in our bubble here in Toronto,” Flyers general manager Chuck Fletcher said. “They’ve found their game very quickly. They play with purpose, structure and identity. They have some skill up front, too. They have three lines that can score. They’re really a good hockey team.”

Vancouver-Vegas hasn't had the chance to become a rivalry yet, since the Canucks missed the playoffs in the Golden Knights' first two years of existence. But the Canucks advanced by eliminating the defending Stanley Cup champion St. Louis Blues, and they have the respect of the top seed in the West.

“What I’ve been most impressed with: They’re a different team than they were prior to the the pause,” Vegas coach Peter DeBoer said. “You see they’ve got a heightened awareness of defending and being harder to play against defensively. And when you add some of the skill and speed and some of the offense that they’re capable of generating, especially their special teams, that’s made them a real dangerous team.”

A condensed schedule to get through the bubble playoffs mean each series has at least one set of back-to-back games, and Boston-Tampa Bay has two. If long-established pleasantries weren't enough to spice up this summer hockey, that'll add some more to the mix, and players are looking forward to going through a rival to advance.

“You go through this, you want to play good teams,” Boston winger Brad Marchand said. ”These are the series that people want to see, and these are the series that guys want to be part of and play in."

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