Sitting on the bench with time winding down in the eighth and final game of the '72 Summit Series, Henderson abruptly stood up and yelled at Pete Mahovlich to come off.
"I felt I had to get on the ice," Henderson recalled recently. "A tie was no good, they were going to claim victory because they had scored more goals than we did. I really wish I had an answer, but I don't. I just felt I had to get out there, I felt I could score a goal.''
He was right, of course.
Henderson fired a rebound past the Soviet Union's Vladislav Tretiak to give Canada a series-clinching 6-5 victory at Moscow's Luzhniki Ice Palace.
Exactly 40 years to the day after that iconic goal, the 69-year-old Henderson and the remaining members of the Canadian squad will cap a month of celebrations with a gala dinner Friday night.
"Thank goodness Peter thought it was a coach yelling at him and came over the boards and I jumped over," Henderson said. "(Yvon) Cournoyer had the far point, I yelled at him and he threw it across but it was a little too far ahead of me and the defenceman tripped me.
"I remember saying, 'We still have enough time . . . ' But before I knew it Phil (Esposito) had whacked it at Tretiak and I got the rebound and shot it once. Tretiak stopped it and then I got the rebound and jumped in the air and we've been celebrating now 40 years.''
Henderson, who has been battling cancer since 2010, was one of Canada's top players in the Summit Series, registering 10 points (seven goals, three assists) in eight games. But his deciding goal remains one of the biggest and most memorable in Canadian hockey history, a fact he didn't really appreciate until watching Sidney Crosby's winning goal for Canada at the 2010 Winter Games in Vancouver.
"I think one of the things we don't do well as Canadians is celebrate a lot of times, but especially with hockey," Henderson said. "When Crosby scored, man, I was jumping up and down and so I understand what Canadians were doing when I scored.''
But Henderson wouldn't have scored if not for Esposito, the heart and soul of the '72 team who fired the first shot at Tretiak.
"I was at the faceoff dot to the right of Tretiak," Esposito said. "(Soviet defencemen Yuri) Liapkin and (Valeri) Vasiliev screwed up and the puck squirted and I was skating backwards to go back and I just shot it at the net.
"Like nine out of 10 times I hit the net, I very seldom missed the net when I had an opportunity to hit it . . . and Tretiak, for some unexplained reason, pushed the rebound straight out and Paul, who had fallen behind the net, got up and came out because they must have lost him, just came out and put the rebound in.''
And while Canada celebrated, Henderson's immediate thoughts turned to his late father.
"My father died in 1968 and he really wanted me to be a hockey player," Henderson said. "I never thought of him the whole series, I was far closer to my mother than I was my father.
"But when the puck went across the line I said out loud, 'Dad would've loved this one,' and there was that touch of melancholy. I think it's that father-son connection maybe. It only lasted for a nano-second and then I just jumped into Cournoyer's arms. Amazing, isn't it?''
There's also a sense of irony that the first player Henderson, a Toronto Maple Leaf, celebrated with was Cournoyer, a Montreal Canadien.
"I could've kissed him at that point," Henderson said with a chuckle.
Goaltender Ken Dryden, another Montreal Canadien, skated the length of the ice to celebrate Henderson's goal with his teammates before the reality of the situation set in.
"I have no recollection except I do remember the celebration of it," Dryden said. "I remember clunking down the ice and being in that pile of celebration and then thinking, 'I've got to get hold of myself, there's still 34 seconds to go, get a grip.'''
Henderson's heroics weren't limited to Game 8. He also scored the winning goals in the sixth and seventh games the Canadians also had to win after falling behind 3-1-1 in the eight-game series.
"It's meaningful to get the last one but when you get three in a row, I mean I was lucky that's for sure, but it was a wonderful experience," Henderson said. "The neat thing for me is I wasn't an all-star, a Hall of Famer at that point but it was really neat to prove I could play at that level and play very well.''
Hollywood couldn't have written it better, Henderson said.
"I'm 69 and I can't think of anybody who has lived a better life than I have, even with cancer," he said. "I wouldn't change places with anybody. Canadians celebrate this, I get it every day and I think it was a meaningful time for Canadians who were alive and can remember at that point.''
Note to readers: This is a corrected story. A previous version said Russia's Vladislav Tretiak instead of the Soviet Union's.