In the fourth and clinching game of the 1970 Stanley Cup finals, Boston Bruin star defenseman Bobby Orr flew through the air, lunged, and fell as he scored the overtime goal against the St. Louis Blues, to give the Bruins their first Stanley Cup in 29 years. The image of Orr sprawled on the ice has become one of the most enduring in hockey history.

Orr’s place in the game is sacred. He is one of that very select group — Maurice “The Rocket” Richard and Wayne Gretzky are two other members — credited with being not just phenomenally gifted, but with changing the idea of how the game was played. Orr rushed, moving at will and with lightning quickness up and down the Boston Garden ice; he had a very hard, accurate shot; he could skate and he stickhandled beautifully. He was an offensive-minded defenseman who controlled the game’s pace at both ends. He displayed the daring — more traditional, defensive-minded observers sometimes termed it “recklessness” — to rush up ice and create havoc before dishing off to one of the forwards or scoring himself. The next generation of brilliant defensemen — most notably the New York Islanders’ Denis Potvin and the Edmonton Oilers’ (and later Pittsburgh Penguins’) Paul Coffey — took their lessons from Orr’s tough but stylish play.

In 1969-70, Orr did the unthinkable when, as a defenseman, he won the scoring title. He set records for most assists and most points in a season. He was the first defenseman in NHL history to score a hat trick in a Stanley Cup game.

Orr led the Bruins to a second Stanley Cup in 1972, and he certainly had a good supporting cast, among them Phil Esposito, Johnny Bucyk, and Gerry Cheevers. But the career of the great #4 was shortened by injuries, probably partially the result of his active style of play. He came back with the Chicago Blackhawks in the 1976-77 and 1978-79 seasons. But he will always be remembered, especially by Boston fans, for the way he singlehandedly took over a game and almost made those in the arena — players, fans — stop and watch and admire. In Orr, they were watching not simply one of the NHL’s greatest players but one of its innovators, as well.