Barca need two points from their remaining four matches to wrest the title back from their arch rivals, who have played a game more and need to win at Espanyol on Saturday to keep the title race alive.
It would be the Catalan club's fourth domestic league title in five years, an achievement that comes close to matching the "Dream Team's" four consecutive triumphs in the 1990s, and their first under new coach Tito Vilanova, who took over from Pep Guardiola at the end of last season.
Atletico have already made sure of third place and a berth in the Champions League group stage.
They will also be looking ahead to their Copa del Rey final clash against Real in just over a week's time but coach Diego Simeone said he and his players would not be distracted by the chance to ensure their city neighbours end the season without major silverware.
"We cannot allow ourselves to be lose sight of the next game because we've never approached things differently, we need to focus on Barcelona," Simeone said.
"We know it will be a difficult game on Sunday but the fans can get together and celebrate making it into the Champions League," added the Argentine, who has transformed the team since taking over midway through last season.
"It will be a challenge and we'll see tomorrow how the lads are feeling ahead of the game."
Real's 6-2 win at home to Malaga on Wednesday trimmed the gap to Barca to eight points and although a win at Espanyol would cut the deficit to five, a Barca victory at the Calderon would give them an unassailable lead as Real will only have two games left and six points available.
Atletico's 3-1 win at Celta Vigo on Wednesday put them 14 points clear of fourth-placed Real Sociedad, who are well placed to secure a place in Champions League qualifying ahead of their game at home to Granada on Monday.
Another league title for Barca would help ease the pain of this month's reverse to Bayern Munich in the Champions League semi-finals, when they crashed to a 7-0 aggregate defeat, their worst result in European competition.
Barca's World Player of the Year Lionel Messi, who had to watch last week's second leg from the bench because of injury, now appears back to full fitness and can add to his incredible tally of 46 league goals for the season at the Calderon.
He is closing in on his record of 50 set last term and is 12 ahead of Real's Portuguese forward Cristiano Ronaldo on the scoring chart.
Barca may have Messi's Argentine compatriot Javier Mascherano available again after he joined his team mates for part of Wednesday's training session for the first time since damaging knee ligaments in the Champions League quarter-final first leg at Paris St Germain.
Vilanova, who is recovering from throat cancer, will arrive back from New York later on Thursday where he has been having medical tests.
"Winning a title is special and the league even more so," midfielder Sergio Busquets said
"It's the tournament that rewards consistency and the most important," added the Spain international.
"What's more, it would be the fourth league title in five years and that would be spectacular."