The 45-year-old winger, who was a member of the Czech's 1998 Olympic gold medal winning team, said he had considered a return to the national team for the Games in South Korea but has not been able to get match fit.
"I was kind of hoping that if I stayed here in the Czech league or somewhere in Europe, I would get used to the bigger ice and if I was going to be good enough to help the team, there was a possibility to play," Jagr told a news conference.
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"But right now, I am not ready, I am not good, I did not play many games, so not a chance."
Jagr joined the Flames earlier this season on a one-year contract, scoring a goal and six assists in 22 games. But the winger has been sidelined since the end of 2017 with a lower body injury that prompted the Flames to release him.
With no other NHL offers forthcoming, Jagr returned home to the team he now owns and where he started his career before the Pittsburgh Penguins drafted him in 1990.
He plans to return to the ice on Saturday for an away game against Benatky nad Jizerou.
Jagr, whose haul of 1,921 career points while playing for nine NHL teams is second only to Wayne Gretzky's total of 2,857, said he wants to lead the second league team to the top division.
Since Jagr announced his return, the team has sold out its games and is considering moving to bigger arenas.
"When I am on ice, I am a player, not the owner, so if I make a mistake, they should treat me as an 18-year old boy," Jagr said.
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