No. 24 Mississippi State is promoting defensive coordinator Zach Arnett to head coach to replace Mike Leach, who died suddenly of a heart condition earlier this week.

Mississippi State was working to finalize a four-year contract with the 36-year-old Arnett, a person with knowledge of the decision told The Associated Press on Wednesday on condition of anonymity because a deal had not yet been completed. ESPN first reported the move.

Leach, 61, died Monday night at a Jackson, Mississippi, hospital after falling gravely ill Sunday at his home in Starkville. Mississippi State has scheduled a memorial service to celebrate Leach on Tuesday at Humphrey Arena on campus. The event will be open to the public.

Arnett was put in charge of the team by Mississippi State officials in Leach’s absence. With the early signing period a week away and the transfer portal active, Mississippi State was motivated to move quickly to put a new coach in place. The Bulldogs also play Illinois in the Reliaquest Bowl on Jan. 2.

Mississippi State is also currently without an athletic director after John Cohen left the Bulldogs for Auburn at the end of October. Longtime Mississippi State athletic department administrator Bracky Brett has been serving as interim AD.

Before Leach’s death, the school was moving to fill its vacant athletic director position before Christmas.

Brett told AP on Tuesday, hours after Leach’s death was announced by the school, that the AD search and next move with the head coach were going to be in the hands of university President Mark Keenum.

Arnett has been Leach’s defensive coordinator since he took the head coaching job at Mississippi State in 2020. His defense ranked fourth in the Southeastern Conference in yards per play allowed this season and fifth in 2020, falling off to 11th in the 2021.

Arnett is a native of Albuquerque, New Mexico, who played linebacker for the University of New Mexico from 2005-08 under coach Rocky Long.

His coaching career began under Long, too, at San Diego State. He spent nine seasons with the Aztecs, rising to defensive coordinator in 2018 and leading some of the top defenses in the Mountain West before joining Leach’s staff.

Arnett being elevated makes him the eighth former Leach assistant to be a head coach currently in major college football.