The next step for Sosunov is to prove he can play consistently in the AHL and move on to where he can one day challenge for a roster spot with the Lightning.
"That was kind of our plan from Day One, to use [last season] as kind of a learning year," Roest said. "Now you can see he's skating better, he's obviously big and strong (6-foot-9, 236 pounds). We are happy with where he is development-wise, but he's going to have to play this year."
Sosunov will begin the season with Syracuse and said he wants to show he's the kind of defenseman Tampa Bay wants in its organization, a player who can be strong in the defensive zone but move the puck forward and contribute offensively.
"I think I'm more than a defensive defenseman," he said. "I have to continue to improve and work to get on the ice. Hopefully I can stay healthy."