Should I be concerned if a job seeker is not focused during the interview?

I construction interviewed an outstanding fit for a hard to fill position. But, when the applicant came in he was poorly dressed, unfocused and seemed completely out of it. I cut the construction interview off rather short and was not sure if I should reschedule another construction interview or rule this construction executive out completely. Everybody has an off day. If this construction executive is an exceptional construction executive, I would consider rescheduling another construction interview. Talk to the construction executive and ask what his assessment of the initial conversation prior to setting another construction interview. Assist by providing insight to the construction executive stressing the importance of communication and presentation skills for this position. If you really feel that this construction executive would be a good fit, then give him another chance to prove himself.