Cesare Prandelli has resigned as Valencia head coach after only three months in the role.
The former Italy boss took over at Mestalla in September after the sacking of Pako Ayestaran, but has failed to improve the club's results.
Valencia – who will now be under the caretaker charge of Voro for the fourth time – are 17th in LaLiga and only outside of the relegation zone on goal difference.
"Cesare Prandelli has communicated to Valencia CF his irrevocable decision to resign from his position as coach," the club confirmed in a statement on Friday, adding that a media conference will be held on Saturday.
Prandelli guided them to just one victory in his eight league matches at the helm, with the 3-2 defeat at Real Sociedad on December 10 proving to be his last top-flight game in charge.
He did guide Valencia through a Copa del Rey tie against Leganes, but has opted to leave nine days after the second leg of that 5-2 aggregate victory amid reports of dressing-room unrest.
The 59-year-old has now had two short stints at clubs since leaving Italy after the 2014 World Cup – his spell at Galatasaray lasted only 147 days.
Valencia struggled to a 12th-placed finish in LaLiga last season after a a turbulent campaign which saw both Nuno Espirito Santo and then his replacement Gary Neville sacked.