The struggling Arizona Diamondbacks fired hitting coach Darnell Coles and assistant hitting coach Eric Hinske on Thursday.
Triple-A hitting coach Rick Short and race production coordinator Drew Hedman were promoted to co-hitting coaches.
Arizona, currently last in the National League West with a 20-43 record, has lost seven straight games and 19 straight on the road. His slip on the road is the longest streak in the majors since 1985.
The Diamondbacks are currently ranked last in the National League with a .231 batting average and fourth-to-last in OPS with .685.
Associated Press contributed to this report.