Rather than retire the No. 7 jersey, the St. Louis Blues honored four former players who wore that number with distinction.
The ceremony was held outside the Scottrade Center, although fans could take their seats and watch on the videoboard, and the quartet later participated in a puck drop at center ice prior to the opening faceoff.
"It's been a good number, but it's really been a great memory to be part of the Blues," Berenson told reporters after the ceremony. "The players, the management, they loved the uniforms. It became a special place."
Berenson, the longtime coach at Michigan, scored a franchise-record six goals Nov. 7, 1968, at Philadelphia and coached the Blues from 1980-82. He's weary of questions about his six-goal game.
"I get asked about it too often," Berenson said. "You've got to have a good night every once in a while."
Unger is fourth on the franchise career list with 292 goals and 575 points, and had seven hat tricks.
"It was an unbelievable time of my life," Unger said. "Thanks for remembering. I appreciate it."
Mullen, who played for St. Louis from 1979-86, was the first U.S.-born player to score 500 goals and 1,000 points. Tkachuk retired last season after spending parts of nine seasons with the Blues and is fifth in franchise history with 208 goals.
Tkachuk, who lives in St. Louis, was minus his front teeth at the news conference, a hazard of the profession.
"I was going to say it feels good to be back, but obviously I haven't left," Tkachuk said. "I love the Blues and we're going to get back to our winning ways."
Berenson and Unger were traded for each other, with Berenson going to Detroit. Unger, known for his flowing blond locks, played in a franchise-record 662 consecutive games.
"I was traded for the icon of the community," Unger said. "I got married here, my kids were born here."
Unger said the iron man streak was a product of his upbringing. A younger sister had polio.
"I never missed a day of school, I never liked to disrupt my life with anything," Unger said. "When I felt bad in the morning I was better off going to practice to sweat a little bit.
"She was in a wheelchair and could never walk, so it was really tough of me to say I've got a sore ankle or a sore shoulder."