"It's been mentioned a few times," Cullen said. "It gets around."
Without Jagr in the League, Cullen is the only 41-year-old remaining in the NHL and is one of just two players who are playing at 40 years of age (Boston's Zdeno Chara will turn 41 later this season).
Cullen said he's watched Jagr's career from afar for a long time. The two were even teammates for one season with the New York Rangers in 2006-07.
"I was so impressed with how much he puts in to taking care of himself and committing to the game," Cullen said. "That was kind of before guys were doing a lot of that. He was really committed to doing what he needed to do. He was there before everybody. His late-night workouts are pretty well documented. It takes a lot to continue to play at that age. What a career he had."
Cullen said he remembered being 14 years old and watching his favorite team, the Minnesota North Stars, lose to the Pittsburgh Penguins in six games in the Stanley Cup Finals.
Jagr was an 18-year old rookie on that Penguins team, scoring three goals and 13 points during Pittsburgh's 24-game playoff run that postseason. That came after a 27-goal rookie campaign, Jagr's first of 17 consecutive 20-plus-goal seasons.
"Thinking he was a big part of that is pretty amazing thinking about how long ago that was. He still played the game at a high level right up until the end. It was quite a career," Cullen said. "You can't say enough. It's not easier to play as guys get older. It's a young man's game now with it getting faster and faster. To play as long as he did is amazing."
Cullen is uniquely qualified to make that statement. So is Wild coach Bruce Boudreau, who has been around some of the game's best as they've played into their 40s. In Anaheim, Boudreau coached Teemu Selanne during his final seasons in the League.
Selanne played at a very high level, scoring 26 goals and 66 points in 82 games as a 41-year-old in 2011-12. He retired in 2014 after playing in 64 games as a 43-year-old.
"I thought he was the most amazing athlete in the world," Boudreau said of Selanne. "You look at every other sport, there's no [43-year-old] man playing at that level. In football, other than Tom Brady, if you're older, you're usually a kicker. In baseball, it's maybe a relief pitcher, there aren't a lot of Nolan Ryans around.
"But to play 15 minutes, in a physical sport, like this at that age is pretty incredible. I don't think people realize how good it is for a Jagr, or a Gordie Howe or Teemu Selanne to do the things at that age, or Matt Cullen, quite frankly."