Hercules have sacked coach Esteban Vigo following Sunday evening's 4-0 home defeat to Osasuna.
That was Hercules' ninth loss in their past 11 games and left the Alicante-based side bottom of the standings following Malaga's win over Espanyol.
The 56-year-old Vigo, whose contract ran until June 2012, led Hercules out of the Segunda Division last season and helped the top-flight newcomers create one of the shocks of the current campaign when they beat Barcelona 2-0 at the Camp Nou in the second week.
That remains Barca's only league defeat of the season, and Hercules followed that with other impressive performances against La Liga's big guns, beating Sevilla and Atletico Madrid as well as holding Villarreal to a draw.
However, since the turn of the year, Hercules have picked up just seven points from a possible 39, resulting in them sliding down the Primera Division standings to last place, where they are now four points adrift of safety with nine games remaining.