The Otago Daily Times also understands former Otago hooker David Latta may be asked to be involved in the coaching team.
Martin (50) will be given a fourth year in the job despite leading Otago to a disappointing 10th in the Air New Zealand Cup.
He had come to the end of his three-year contract at the end of this season, and was forced to reapply for the advertised position.
Latta, former Otago assistant coach Phil Young and Alhambra-Union premiership-winning coach Mike Moeahu all applied for the job.
But after interviews over the past couple of weeks it is believed Martin will be named today as head coach for another year.
Latta, who played 161 games for Otago and has been involved with Otago Country over the past three years, may be asked to be part of the coaching team in some regard.
Martin's job is only for one year, with the structure of the Air New Zealand Cup set to be changed in 2010, when the job may become part-time.
Martin has coached Otago for the past three years.
The side made the semifinals in 2006 and the quarterfinals in 2007, and then fell to 10th this season.
Martin had indicated he was keen to keep the job and wanted to continue the work he had done in the past three years.
He said in an interview last month he wanted to come back and work with players he had introduced to the team over the past couple of seasons.
Martin is the Highlanders' assistant coach, employed by the Highlanders franchise.
He is the defence coach for the franchise.
Carvell, a forwards coach, did not seek the head coaching position, preferring instead to hunt the assistant coaching position.
Carvell, a former coach of Harbour and Otago age group teams, joined Otago as assistant coach halfway through the 2007 season, when Glenn Moore was appointed the Highlanders coach.
