Denis Potvin #5, former captain of the New York Islanders,...

Denis Potvin #5, former captain of the New York Islanders, addesses the fans as former general manager Bill Torrey (R) looks on during a ceremony honoring the 25th anniversary of the Islanders first Stanley Cup victory, before the Islanders game against the Philadelphia Flyers on March 4, 2006 at the Nassau Coliseum. Credit: Getty Images/Bruce Bennett

The upset playoff losses to the Maple Leafs in 1978 and the Rangers the following year shook an Islanders organization that believed it was poised for greatness.

In particular, the fun-loving Clark Gillies felt the doubt. The “C” he wore as captain those seasons began to hang heavy in his thoughts.

“You kind of say, ‘Am I doing the right job? How much am I to blame for this? Did I not motivate the guys? Did I not do what I could while I was wearing the ‘C?’ ” Gillies recalled to Newsday last month. “Maybe it was more of a superstitious thing than anything else. We haven’t won. Maybe we’ve got to give it a try with somebody else.”

So 40 years ago this month, it was the brasher, more outspoken Denis Potvin who was handed the Stanley Cup first to cap his first season as the Islanders’ captain. He wore the “C” until 1987, through five straight berths in the Stanley Cup Final and four Cup wins. Potvin’s eight seasons wearing the “C” still is the longest tenure of the Islanders’ 15 captains.

“We all recognized Denis as a leader, let alone the captain,” Bryan Trottier recently told Newsday. “But Denis embraced the captain’s role. He really embraced it. An ‘A’ or a ‘C,’ when you embrace it, it doesn’t feel heavy on your jersey.”

After the two playoff upsets, Gillies approached coach Al Arbour about his concerns. Arbour went to general manager Bill Torrey. There was a long list of viable candidates, including Trottier, Bob Bourne, Bobby Nystrom among them.

But just before the start of the regular season, management named Potvin, who turned 27 in the season’s first month, as the Islanders’ third captain after Ed Westfall (1972-77) and Gillies (1977-79).

Former Islander Clark Gillies is honored prior to the game...

Former Islander Clark Gillies is honored prior to the game against Chicago at Nassau Coliseum on Dec. 13, 2014. Credit: Getty Images/Bruce Bennett

“Clarkie is the one who announced he was going to give up the captaincy,” Potvin told Newsday in April. “We knew there was going to be another captain that was going to be chosen. Clarkie had been voted by the players, so he was a very popular guy in the dressing room. The next time around, it became a management decision. Accepting the captaincy to me was just fine. I looked forward to wearing the ‘C.’ ”

Potvin, one of the best defensemen in NHL history, and Gillies, a prototypical power forward, are Hall of Famers, blessed with superior skills, physicality and strength. Both are revered by their former teammates. But they had disparate personalities.

Gillies was happy to be Joe Long Island, away from the glitz that New York City offered. Potvin was comfortable with the spotlight.

“Clark is a fun-loving, happy, joking tough guy and he liked all the players. He has compassion,” Nystrom, Gillies’ longtime road roommate, told Newsday in April. “Denis is a little more aloof and wouldn’t get bothered by certain things that maybe Clark would. I thought it was a real good move. Clark, listen, I love the guy, but he wanted to be liked by everybody. So I don’t think he had the ability to go to someone and say, ‘You haven’t been playing all that well.’ Denis would have a little bit more of an ability to deal with a situation like that.”

“Denis Potvin came in and he thought he was as good as Bobby Orr,” Glenn “Chico” Resch told Newsday last month. “A lot of his stats showed if he wasn’t the best, he was certainly a close second to Orr. But Denis had a confidence that would step over into a little bit of arrogance. It was an era where Joe Namath and all the New York guys were outspoken. It wasn’t the same 'everybody stay humble and keep your mouth shut.' ”

Potvin certainly played with an edge.

“Denis was vicious,” Gillies said. “One of the best hip checks I’d seen. If you weren’t careful, you were going to the orthopedic surgeon the next day. Denis was out there to hit and, if it happened and the guy got hurt, it didn’t bother him one bit. I don’t think it did, anyway. This is all on top of being one of the most skilled defensemen you’ve ever seen. He had that mean streak far and above what any of the other guys had and it really set him apart from the other talented defensemen.”

Neither Potvin nor Gillies flourished as the Islanders, who had won the Presidents’ Trophy with the most points in the NHL in 1978-79, struggled through much of the 1979-80 regular season.

Potvin, beset by injuries, had eight goals and 41 points in 31 games, all career lows, after compiling career highs with 70 assists and 101 points the previous season. Gillies had 19 goals and 35 assists in 73 games after notching 35 goals and 56 assists in 75 games in 1978-79.

But both had strong postseasons, and the Islanders won 10 of their first 12 playoff games en route to a six-game win over the Flyers in the Stanley Cup Final.

Gillies had six goals and 10 assists in the 21 playoff games. Potvin had six goals and 13 assists. That included two goals — one the overtime winner — and an assist in the Islanders’ 4-3 victory over the Flyers in Philadelphia in Game 1 of the Cup Final. He also had two goals and two assists in the Islanders’ 6-2 win in Game 3, the first-ever Cup Final game at Nassau Coliseum.

Potvin added a power-play goal in the 5-4 overtime win in Game 6 at the Coliseum on May 24, 1980, then was handed the Cup after the Islanders clinched their first title.

Gillies joked that “I did say, after we won the Cup, maybe I should have waited one year” to relinquish the captaincy.

He added, somewhat jokingly, that being the captain was costing him too much. He organized the team parties and fronted the money, though he was not always repaid by his teammates.

In contrast, Potvin said he just went to Arbour to pay for the parties.

“It was a good transition,” Trottier said. “For Clark, it took a lot of courage. It didn’t change how the team felt about him. It probably empowered him even more.”

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