The team known as "yellow submarine" after their canary-coloured shirts are second from bottom in La Liga with just under half the season gone and face a crucial match at home to fellow strugglers Sporting Gijon on Monday.
They were beaten in all six of their Champions League Group A games this season, scoring just two goals and conceding 14, and their elimination from the King's Cup at the hands of third-tier Mirandes last month prompted the dismissal of coach Juan Carlos Garrido and the promotion of B-team boss Jose Francisco Molina to replace him.
As well as the departure of their best player, midfielder Santi Cazorla, to Malaga in the close-season, they have suffered a spate of injuries to key players, including first-choice forwards Giuseppe Rossi and Nilmar.
However, there is also a sense of a club in decline, struggling to stay competitive in a league where Real Madrid and Barcelona, the world's richest clubs by income, take the lion's share of revenue from audiovisual rights.
"The first thing to do is to accept the reality because we are second from bottom and that means we all have to give more, individually and collectively," Lopez said at a news conference on Wednesday.
"I would like to see a lot more pugnacity," the former Spain goalkeeper added.
"We have a very young squad, with a good atmosphere, but maybe we need a bit more character.
"We are living on the edge and we need the real men to stand up and be counted."
BARCA HIGH
The latest round of matches was postponed from the opening day of the season due to a strike called by the players' union (AFE) over unpaid wages.
The games originally scheduled for this weekend are due to be played at the start of May.
In between the two legs of their King's Cup quarter-final tie, leaders Real and second-placed Barca are at home to Athletic Bilbao and away at Malaga respectively on Sunday.
Barca are on a high after coming from a goal down at Real's Bernabeu stadium to win the first leg 2-1 on Wednesday and host their great rivals for the return leg at the Nou Camp next Wednesday.
Third-placed Valencia, who host city neighbours Levante in a cup quarter-final first leg later on Thursday, play at Osasuna on Sunday having slipped seven points behind Barca after last weekend's 1-0 home defeat to Real Sociedad.
Unai Emery's side were boosted by the news on Wednesday that their Argentina midfielder Ever Banega had agreed to extend his contract until the end of the 2014/15 season.
Sevilla coach Marcelino is under pressure ahead of the local Andalusian derby at Real Betis on Saturday.
Sevilla are on a run of three defeats and a draw and have dropped to seventh, putting their bid to qualify for Europe next season in peril, while Betis have climbed to 11th following three straight wins and
