It's pretty simple - Lazar will be given the opportunity to outplay Condra in preseason and probably for a 9 game stretch. if he does, he will secure a spot with the Sens for sure. If it is close between them, I still think he makes it. If he struggles at all (quite possible), he'll likely be sent down. But he'll be given a solid opportunity, likely getting better ice time and linemates than Condra during preseason, as an extended audition to show he belongs or not (The team knows what Condra brings to the table already).
With Ryan, Stone and Neil locked in on the right side, Condra is really the only guy he needs to show he is an upgrade over, and given Condra's versatility (can play LW too), it is not a big deal, as he'll find a place in the line-up on many nights whether Lazar is here full time or not.
Seems like a good chance, but the spot won't be given to him. There is also the chance he gets hurt or banged up, in which case he might be sent back. He basically only played very briefly with the team last year before hurting his shoulder, so he needs to show he can stay healthy playing against men too.