The Boston-New York sporting rivalry, one-sided though it often is (Hub fans invariably care more about beating anything NYC than the other way around), has traditionally taken a backseat on ice. Still, it beggars belief that Bruins v. Rangers — a battle of Original Sixers separated by just 200 miles — has become such a non-entity, largely because the two combatants have not played a single playoff series since 1973, despite having always competed together in the Eastern Conference, or some randomly named facsimile thereof.

That streak ends Thursday night with Game 1 of the NHL’s Eastern Semifinals at the TD Banknorth Garden, and perhaps it will light a fire going forward. If nothing else, it will serve as a stirring flashback for hockey fans of my vintage who remember a time when this was a proper rivalry and home teams wore dark uniforms in their own barn — a practice that had long prevailed back in the day, was abandoned by the NHL in the mid-1970s, but has recently been restored.

The Bruins’ blood rivals are, of course, the Canadiens, whose decades-long torture of Boston peaked just as the Rangers rivalry fell away, in the late 1970s. Those Montreal teams were all-timers, star-studded winners of four straight Stanley Cups (1976-79). The B’s, though very good throughout the ‘70s, simply could not slay them. Even in their heyday, when they netted a pair of Cups, in 1970 and ‘72, the Bruins were never obliged to beat the Canadiens in a playoff series.

Montreal had many rivals during that period, and it only stoked Boston passions further that peut-être Les Canadiens didn’t care that much about beating the Bruins. Today, recent form and some incendiary incidents of thuggery have perhaps stirred in Montreal fans a hatred that matches that of Bruins Nation.

[Indeed, much of Canada has every right to loathe the current B’s following their organ-removing defeats of heavily favored Vancouver in the 2011 Stanley Cup Finals, and Monday’s unlikely Game 7 dispatch of Toronto’s Maple Leafs, in overtime — the Bruins had trailed 4-1, with just 10 minutes remaining. No Canada-based club has won the Cup since 1993, a fact that continues to gall hockey purists (read: 90 percent of the population) north of the border. Maybe derision of the current Bruins can be that one elusive thing all of Canada can agree upon…]

The Bruins of the early 1970s were not so villainous. They were Big and Bad, in an admirable way, and the Rangers — more of a finesse team, built on the refined skills of Rod Gilbert, Jean Ratelle, Brad Park and Vic Hadfield — proved compelling foils. Boston beat them to win the Cup in 1972. Their last playoff meeting was a Ranger victory, the 1973 conference semifinals. As a young Bostonian, I vividly remember resenting the Rangers for unseating the defending Cup champions, a loss that kicked off one of the most frustrating runs of near misses in hockey history. (Boston would lose the 1974 Cup final to Philly before dropping a dizzying succession of playoff series to Montreal, each one more gut-wrenching than the last.)

But any resentment of the Rangers didn’t last.

Terry O’Reilly and his crew famously went into the stands at Madison Square Garden to punch up some Rangers fans in December 1979, but the lack of playoff confrontation — who could imagine it would last fully four decades? — effectively defused the rivalry. The 1975 and 1976 trades that shipped Phil Esposito, Ken Hodge and Carol Vadnais to New York, in exchange for Ratelle, Park and “Nifty” Rick Middleton, further blurred the line between bitter enemy and mere foe.

Montreal became the fixation.

It’s funny how that works: The best rivalries become a sort of long-term competitive obsession, to the exclusion of teams that might well be torturing or otherwise beating you in the moment. Boston endured 39 years between titles (1972-2011), and in that seemingly interminable span they were beaten back by several great teams of longstanding: the Islanders of the early 1980s, Gretzky’s Edmonton Oilers… Yet we Bruins Fans never stopped hating on the Canadiens exclusively.

[Another great piece of nostalgia prompted by this year’s playoffs: the return of the Islanders after a long post-season absence. Just seeing their uniforms, admirably unchanged from the glory days, stirred strong memories of Bossy, Gillies, Trottier, Nystrom, Smith and Resch. The Nassau County Coliseum — scene of so many vintage Bruins telecasts delivered via rabbit ears and Channel 38 — remains impossibly small, dark and retro. Their current star, John Taveras, wears no. 91 and, for a brief moment during their first-round loss to the mighty Penguins, I mistook him for Butch Goring…]

The Rangers famously went 54 years without a Stanley Cup before winning one in 1994 (deploying a goodly number of former Oilers, it must be said), and I’ve no idea whether Ranger fans brought with them on that long and painful journey a particular rival, or developed one. Maybe, for a time, it was the Islanders. Maybe it has become the Washington Capitals, whom the Rangers seem to have faced, in the playoffs, every year for the last two decades (though it’s hard to develop a rivalry with a team that has never won anything, ever).

If it’s been the Bruins all along, I feel sorry for them, because we never really noticed.