With Lionel Messi injured and Brazil striker Neymar yet to arrive, Barcelona still had little trouble beating 10-man Espanyol to leave the Spanish league champions only one victory away from equaling the Spanish league's record point haul.
Forward Alexis Sanchez scored in the 14th minute after a passing combination with David Villa. After the visitors had squandered several opportunities substitute, Pedro Rodriguez sealed the win four minutes from time after Espanyol midfielder Mubarak Wakaso received a second booking in the 80th.
Barcelona has 97 points and can match Real Madrid's milestone of 100 from last season with a victory over Malaga in the last round.
The 21-year-old Neymar said on Saturday that he would be leaving Brazilian club Santos in the offseason to play for Barcelona for the next five seasons.
"Neymar is the player we were looking for," said Barcelona coach Tito Vilanova, adding that the goal of reaching 100 points was now his team's focus with the league trophy wrapped up.
"Even though it isn't a title, we will try to reach it."
Also Sunday, which featured all 10 matches played simultaneously, Real Sociedad fought back to draw 3-3 with Real Madrid but lost its hold on fourth place and the last Champions League berth after Valencia downed Granada 1-0.
Madrid coach Jose Mourinho didn't speak to the media after the match, maintaining his silence since club president Florentino Perez announced earlier this week that the Portuguese manager would be leaving after a season without a major trophy.
"Mourinho is a great coach," said Madrid defender Marcelo. "He has helped me a lot and I wish him well."
Manuel Pellegrini coached his last match at Malaga's La Rosaleda in a 3-1 win over Deportivo La Coruna. The Chilean is expected to move to Manchester City.
Osasuna will remain in the top flight after rallying to beat Sevilla 2-1, leading its fans to storm the pitch in Pamplona.
Real Betis rolled over Real Zaragoza 4-0 to rise to seventh place behind Malaga and the Europa League positions.
Rayo Vallecano downed Getafe 2-1 to seize the advantage in the fight for a Europa League spot.
Athletic Bilbao's farewell to San Mames Stadium was spoiled by a 1-0 loss to Levante after Juanlu Gomez grabbed an injury-time winner. San Mames will be torn down and replaced by a modern facility after 100 years as Bilbao's home ground.
No team has yet been relegated. Deportivo, Celta Vigo, Zaragoza, and Mallorca are all in danger with the bottom three destined to go down after the final round.
Last-place Mallorca drew 0-0 at Atletico Madrid. Atletico defender Filipe Luis reportedly was taken to hospital after receiving a knock to the head.
Celta Vigo's 2-0 win at Valladolid was also dampened by goalkeeper Javi Varas' injury to his right arm that appeared to break during a gruesome fall.
Alexis confirmed his resurgence over recent months with perhaps his best goal in his two seasons at Barcelona, dribbling sleekly before a one-two passing combination with Villa to score in the 14th minute.
Espanyol was fortunate not to fall further behind, with Cesc Fabregas hitting the post and Villa missing from close range, before Pedro clinched the win off Xavi Hernandez's pass.
Madrid is on track for its most distant finish in La Liga since 1995-96, when it wound up in sixth place, 17 points behind champion Atletico. The 15-point gap with Barcelona would be the most Madrid trailed its rival at a season's end since the Spanish league switched to three points for a win in 1995-96.
Sociedad dominated Madrid in the first half, but went into halftime a goal down thanks to a defensive blunder by the hosts and Diego Lopez's inspired goalkeeping.
With star forward Cristiano Ronaldo forced to watch from the stands with a back problem, Madrid's attack was toothless. Yet little did that matter when Sociedad defender Mikel Gonzalez gifted Gonzalo Higuain the ball with a horrible pass, and the Argentine sized up goalkeeper Claudio Bravo and slotted in the sixth-minute opener.
Sociedad surged forward and went close several times, only for Lopez to save Antoine Griezmann's header in the 19th and deny Imanol Agirretxe shortly afterward.
Madrid looked set to ease to victory in Mourinho's second-to-last game when Kaka set up Jose Callejon to double the lead in the 57th.
Sociedad, however, never gave up and Xabi Prieto pulled one back in the 64th by stroking in a penalty after Sami Khedira handled the ball in the area.
Griezmann volleyed in a cross from Carlos Martinez to make it 2-2 in the 78th, with the game swinging back in visitor's favor after Khedira scored from a pass by Mesut Ozil two minutes later.
Sociedad had the last word when Prieto's header went over the goal line just before the final whistle. That gave the veteran midfielder five goals in two games against Madrid this season.
Valencia leads Sociedad by two points heading into the decisive round.