Mathias is now in pole position to get the job on a full-time basis. Steve McMahon, John Aldridge and Frank Stapleton have all thrown their names into the hat.
Rumours over the weekend suggested that Wright left because the chairman wanted his son, also called Stephen, to be a regular first-team member.
Both parties issued conflicting comments, with Chester claiming the exit was for `non-footballing` reasons and Wright saying it was `totally for footballing reasons`.
Vaughan said: “Mark Wright walked out of the club, it’s as simple as that. Mark Wright resigned from the company and we’ve accepted his resignation. Mark walked away from the club because of a non-football-related matter, but I’m not prepared to elaborate on that any further.
“I’m sure Mark Wright will come back from this and he will manage in the Premier League one day. He is a good manager, but for people to be singling out his dismissal as a football-related matter regarding my son is an absolute joke.”
“I’ve made a decision that is in the best interests of the football club. At the end of the day, Mark and I are two control freaks, but I’ve come out on top on this one.