Voro has been named interim Valencia coach, with Phil Neville as his assistant, following the resignation of Nuno on Sunday evening.
Nuno announced his departure following Los Che's 1-0 loss to Sevilla, but said he had already informed chairman Peter Lim of his decision prior to kickoff.
In their first formal statement regarding affairs on Monday evening, Valencia said Voro would take charge until a permanent successor is found.
TRAINING SESSION | @valenciacf undertake first training session of the week -> https://t.co/hLIQyF7lkb pic.twitter.com/Q2twTxaTLw
- Valencia CF English (@valenciacf_en) November 30, 2015
"Nuno Espirito Santo has stepped down as head coach of Valencia Club de Futbol by mutual agreement with the club," the club said.
"The club wishes to thank Nuno and his technical staff for their work over the past 18 months.
"Salvador Gonzalez 'Voro' will be appointed as the interim head coach, supported by Phil Neville and the club technical staff. Voro will take charge of the first team pending the appointment of a new head coach."
Voro, who made more than 200 appearances for Valencia as a player, has twice taken caretaker charge of the club before.
He was joined by Neville, the former Manchester United first-team coach, in leading a training session on Monday.
Nuno, 41, leaves the side ninth in Primera Liga and third in Group H of the Champions League, still with a shot of progressing to the knock-out stages.
However, the Portuguese said expectations had not been met as he bid his farewells.
"We are all in agreement that the current situation is not good, and that we must all do what is best for the club; this has always been my intention," he said.
"I want to thank all the players who I have managed at the club for their work. I also want to thank Peter Lim, who is - and will continue to be - a friend of mine, and the fans of Valencia CF.
"I ask that the fans continue to support the youngest squad in La Liga. Tomorrow we will give more details. I understand that the issue is pertinent, but I do not want to say too much in this regard."