The person spoke on condition of anonymity to The Associated Press because the deal is only agreed upon and not finalized.
The embattled coach takes over for Tim Miles, who left for Nebraska last month after leading the Rams to the NCAA tournament.
Eustachy is coming off a season in which he guided Southern Mississippi to its first NCAA tournament appearance since 1991.
It's been a long road for Eustachy, who has rebuilt and restored his career in eight seasons at Southern Miss. Eustachy was a coach at Iowa State over a decade ago before his dramatic downfall. He resigned in 2003 shortly after photos of him partying with students surfaced.