Safety Harrison Smith (center) is a member of the Vikings' Donut Club. Matt Marton USA TODAY Sports

The Minnesota Vikings have a Saturday tradition that has dated back to former quarterback Gus Frerotte's days with team (2003-04, '08).

It's called Donut Club, according to ESPN's Ben Goessling, and it has become a serious part of the Vikings' game-day preparation.

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"For me, it starts my routine for a game, as stupid as that sounds," safety Harrison Smith said, per ESPN.

Vikings athletic trainer Eric Sugarman -- yes, Sugarman -- regularly Tweets out photos of the club, which exceeds 20 members in this one from Oct. 3.

The members with the gray "Vikings Donut Club" t-shirts are the more established members, according to ESPN. New members have to prove their dedication to the club before receiving an official shirt.

Defensive end and veteran member of Donut Club Brian Robison says the Vikings tradition has helped build a brotherhood, per ESPN.

"You want to know the guys you're playing with," Robison said. "At the same time, you want to make this game as much fun as you possibly can, because there's times where it can be a grind. It's just a way for us to come in, have fun with each other and have a good time."

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