Los Rojiblancos head into the final round of matches three points clear of the defending champions and needing only a draw to secure a first league crown since 1996.
And Simeone stressed at his pre-match press conference on Friday that his players must not change their game-plan for the winner-takes-all finale.
"We have always kept the same identity," he said. "I do not think this will change for the last game.
"Personality will be important. To have arrived at this point, we have put in a lot of work and effort. It has not been easy, but we are here on merit."
The capital club will have Diego Costa back in contention after he missed last weekend's 1-1 draw against Malaga with a hamstring strain.
Simeone said his top scorer had "no problems" and was fit to start.
"I have very nice feelings - it's a big game," the Argentinian added. "We go there with intent and desire to compete. Hopefully the team will be prepared to show that on Saturday.
"Barcelona never stopped competing. That allows them to have this possibility. They are always a dangerous team."
Barca too received good news on the injury front on Friday morning as Gerard Pique (hip), Jordi Alba (thigh) and Neymar (foot) were all given the medical green light to play after coming through training unscathed.
Coach Gerardo Martino will have all first-team players at his disposal, bar goalkeeper Victor Valdes, who continues his recovery from a knee injury.
"Neymar, Pique and Alba have worked very hard to return," Martino said. "Now we'll see if they play. It's now about one game - not about six in a row."
The Catalan outfit, whose players and staff congregated on Thursday for an emotional farewell to retiring club captain Carles Puyol, were boosted on the eve of the match by the news Argentina forward Lionel Messi had agreed terms on a new deal.
"It is a very personal matter and it should give peace to him and especially to the club, who can continue to count on the best player in the world," Martino said.
Martino's future has been the subject of much speculation of late, with reports suggesting he will be replaced by Celta Vigo coach Luis Enrique at the end of the campaign - despite having signed a two-year deal when he succeeded Tito Vilanova last summer.
The Argentinian has on numerous occasions this term vowed to honour his contract in Catalonia, but, with Luis Enrique announcing on Friday lunchtime that he will leave his role at Celta at the end of the season, Martino's future will again be under the spotlight in the coming days.
But he remained focused on Friday as he looked ahead to his side's biggest match of the season.
"I wish with all my heart for the club to become champions, but in my career there will not be a phenomenal change," he said. "I decide what I want to do, and no title will change me.
"I will value my time at Barca more as time goes by, rather than while I'm still here.
"There is not a clear favourite for the game. I am approaching the game with a lot of tranquility.
"I would like to win La Liga for the players. It has been a very difficult year for them.
"It's a chance to win a trophy, against a direct rival, and at home. If this team wins La Liga, it'd be their first one as normal people - hard-fought. The others were won by extra-terrestrials."
Whatever the future holds for Martino, he wants to end this season on a high in memory of Vilanova, who lost his battle with cancer last month.
"Tito's passing was my worst moment as Barca coach," he said. "I hope the best moment will be tomorrow."
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