Nikolai Knyzhov has been released from his professional tryout contract with the Penguins after failing to secure a spot on the NHL roster. The 26-year-old undrafted defenseman, who previously played for the Sharks, did not see any action in the Penguins' preseason games. With a competitive defensive lineup, Knyzhov was unable to compete effectively for one of the final roster spots, which are highly contested among several players.