Barcelona and arch-rivals Real Madrid played out a 1-1 draw in the first leg of their Copa del Rey semi-final tie at the Bernabeu on Wednesday, with reports afterwards suggesting Barca forward Lionel Messi had labelled Madrid's assistant coach Aitor Karanka "(Jose) Mourinho's puppet" in the tunnel at the end of the game.
Madrid-based sports daily Marca also claimed that Messi had confronted Madrid defender Alvaro Arbeloa in the car park after the match.
Barca hold a 15-point advantage over the champions in La Liga, though, and Roura was keen not to be distracted by any off-field matters ahead of the trip the Mestalla.
Speaking to the press in the absence of Tito Vilanova with the head coach having remained in New York to continue his cancer treatment, Roura said: "We do not think about these issues. We just talk about the game against Valencia.
"If we get the win against Valencia it will be an important step, but it will be a difficult game.
"It is one of the most complicated places to visit, a very difficult place to go. During the last years we have won a few times there. They have improved with Valverde and are a very dangerous team."
When pressed, he reiterated: "I will not say anything on the subject of Real Madrid. We're not going to get into media games. We talk about football and the game on Sunday. We do not talk about other things."
Vilanova, who was diagnosed with cancer in December, travelled to the United States for treatment after Barca's 3-2 defeat at Real Sociedad on January 19 and has decided to remain there on the advice of doctors.
"The players know this is a special situation," said Roura, whose side beat Osasuna 5-1 at the Nou Camp last weekend. "They deal with it in a spectacular way."
Alexis Sanchez's form has come under the spotlight with the Chile forward having failed to find the net in 14 league appearances this term, but Roura has no worries over the 24-year-old's form.
"We have no concern with him," the Barca number two added. "He's a very important player for us, with an irreproachable attitude. He's going through a rough patch in front of goal, but these things change. We are delighted with him."
Seventh-placed Valencia could have Roberto Soldado and Dani Parejo back for the visit of Barca as they try to narrow the gap on the top four.
Ernesto Valverde's men moved to within two points of the Champions League places thanks to a come-from-behind 3-2 win at Deportivo La Coruna last Saturday, and the former Espanyol boss will have close to a full complement of players to choose from as Sergio Canales and David Albelda are also fit for selection.
Veteran midfielder Albelda has called on Los Che to approach the game positively despite the daunting task ahead.
"It's a challenge for us to play against the best team in the world," he said. "We face the game with hope - if we did not, it would be a problem."
This season looks set to be Albelda's last at the Mestalla, with a move overseas looking a distinct possibility for the 35-year-old in the summer.
"In my head I'm going to finish the season with Valencia and then 95 per cent I will leave," he said. "Right now I do not know the options I have."