The Copa del Rey winners have slipped to five defeats in their last six games and face the prospect of dropping into the second division if they fail to turn things around with three games to go.

They lie 15th in the standings, two points above the relegation places and one above their visitors.

Playing at the intimidating Mestalla would normally be considered a boost but Valencia have the Primera Liga's worst home record, with five wins, three draws and nine defeats in a dismal campaign.

This season the club has been rocked by the sacking of two coaches, the exclusion of three long-standing regulars and woefully inconsistent form.

After last weekend's humiliating 6-0 defeat against Barcelona at the Nou Camp, angry supporters barracked and insulted the players. A small section of fans even continued the abuse at Monday's training.

"Anyone who loves Valencia must be intelligent and get behind the team for these remaining matches," said Marchena.

"We must be focused 100% on Wednesday's game. We understand the situation we are in and we don't need to lose energy worrying about the fans' reaction.

"The game against Barca was a disaster for a number of reasons but we have to forget about it and look ahead now."

Many eyes will be on Valencia's top scorer David Villa, who has scored a disappointing 13 goals this season, as he meets his former club amid speculation he is on the verge of a move to newly-crowned champions Real Madrid.

Coach Salvador Gonzalez Voro, Valencia's third this season, admitted to being in a "state of shock" after Sunday's drubbing and promised his third game at the helm would produce the right response.

"On Wednesday we have the chance to make up for it. It was another chance gone but we still have three left to play and our destiny is still in our own hands," he said.

Like Valencia, Zaragoza started the year as potential title challengers only to find themselves caught up in the relegation battle.

Their fourth coach, Manolo Villanova, has managed to engineer a mini revival over the last month to haul them out of the bottom three, and they have taken eight points from the last 12.

They are just below Valencia in 16th place after a 94th-minute winner from Roberto Ayala gave them a 1-0 home triumph over Deportivo la Coruna on Saturday.

The pressure on the players was there for all to see as the experienced Argentina international finished the game in tears and told La Sexta television: "We gave our all and rose to the challenge.

"These fans deserve it. But it's only one victory and we have to carry on fighting."

Midfielder Alberto Zapater and defender Sergio Fernandez are suspended.