Todd told BBC Spotlight: "We are currently interviewing, and there are some interesting names on the list."
"I will not be drawn into naming names, suffice to say some of the names will not be a surprise to most of our fans."
We will not be rushed into announcing the name of our new manager
Keith Todd
Amongst the favourites to take up the post are Steve Cotterill, Paul Jewell and George Burley.
Todd said: "We will not be rushed into announcing the name of our new manager as we want to be as thorough as possible in selecting the right man.
"But we are eager to have him in place for the pre-season programme."
In May, Todd told BBC Spotlight that he is not expecting head coach Mariner to leave the club after they appoint a new manager.
The Argyle director said he does not think the former England striker will see the move as a demotion.
"Paul is in the job that he was brought in for, and this has been done all cards face up on the table," he said.
Source: BBC Sport
Source: BBC Sport