The Basque side moved up to fifth in the Primera Division table and into the Champions League places - subject to Malaga's European ban being upheld - after beating Atletico Madrid at the Vicente Calderon on Sunday, breaking Diego Simeone's side's 100% home record in the league.
However, the French coach believes it is still "too soon" to talk about Europe.
"The victory over Atletico will help us to grow and have more confidence in ourselves, but the game with Valladolid is another game, another problem," he said at the pre-game press conference.
"There is still a long way to go in the season and there are many points to compete for, and it's still too soon to talk about the Europa League or the Champions League, what we must do is win this game."
The Frenchman also emphasised that Valladolid would be no easier to beat than Atletico.
He warned: "It will be just as hard a match as the one with Atletico and it would be a mistake to think otherwise.
"Valladolid combine defensive balance with quality in attack and they will come here with a careful plan and keen to get a positive result, just like we did in the Calderon."
Valladolid coach Miroslav Djukic has declared that his team must put in a bold performance at Anoeta if they are to come away with anything.
He told reporters: "We must be brave and go for them. They [Real Sociedad] are a very attacking team but they are also balanced."
And he did not rule out his team getting a positive result, despite Real Sociedad's strong performances so far in 2013.
"They have been doing very well but we are also a tough nut to crack," said Djukic.
Winger Daniel Larsson will miss the match after tearing the adductor muscle in his right leg in last weekend's 1-1 draw with Malaga. Djukic indicated that Larsson's place in the starting line-up could be taken by Valdet Rama, although some doubts remain about the player's ability to play 90 minutes.
Javi Guerra, who missed last weekend's 1-1 draw with Malaga due to injury, is available for selection again.