Lee Williams has rejoined the club to become the new Head Groundsman, taking over from Chris Bailey.
Lee (pictured with Chief Executive Neil Joy) is no stranger to Boundary Park, assisting Chris with the pitch for his former company Sherriff Amenity.
He was also head groundsman before leaving the club in 2011.
Speaking about his new role, Lee said: "I'm happy to be back at the football club in a permanent capacity.
"I'd like to thank everyone at Sherriff Amenity for their help and I can't wait to get started with Oldham Athletic."
Chief Executive Joy added: "I'm delighted Lee has decided to rejoin the club as head groundsman.
"The role is often undervalued at clubs so it is important to get the appointment right.
"Lee has a tremendous attitude and I'm looking forward to working with him.
"The club would like to also place on record their thanks to Chris Bailey and wish him well for the future."