Dragons have announced they have parted company with defence coach Hendre Marnitz.
Marnitz joined the region in August 2017 but the region have conceded 127 tries in 29 league games since his appointment.
Dragons head coach Bernard Jackman will initially take on the defence role.
A Dragons statement said: "Following the region's recent run of form, a decision has been made to make a change to the backroom team."
Managing director Mike Davies added: "On behalf of the Dragons I would like to thank Hendre for the contribution he has made to the team and wish him well in his future endeavours."
Dragons only managed two wins in 21 Pro14 games in the 2017/18 season and are currently bottom of Conference B in this campaign after eight matches.