Lionel Messi scored his 425th goal on his 500th Barcelona appearance to help his side to a 4-0 victory against Real Betis.
Luis Suarez and Neymar also shone as Barca signed off a memorable 2015 with a comfortable win that keeps them top of the Primera Division.
The Catalans took the lead after 29 minutes as Betis defender Heiko Westermann inadvertently sent the ball into his own net after Neymar had hit the crossbar from the penalty spot and moments later the Brazilian laid a pass on for Messi to score on a landmark appearance for the club.
Suarez added two further goals in the second half, while Neymar was unfortunate not to get on the scoresheet, hitting the woodwork for a second time later on.
Luis Enrique's side stay joint top of the Primera Division with Atletico Madrid heading into 2016 but have played one game fewer than Diego Simeone's men, who left it late but eventually saw off local rivals Rayo Vallecano 2-0 thanks to goals by Angel Correa (88) and Antoine Griezmann (90).
Cristiano Ronaldo helped ease the pressure on boss Rafa Benitez as his two goals inspired Real Madrid to a 3-1 win over Real Sociedad.
The Portuguese missed a penalty and then scored from the spot to give Madrid a deserved first-half lead which was quickly cancelled out at the start of the second period by Bruma.
But Ronaldo volleyed home from a corner to restore Madrid's lead and then substitute Lucas Vazquez sealed the points with a close-range finish.
Celta Vigo lost ground on the top three as Raul Garcia struck the only goal of the game to earn Athletic Bilbao a 1-0 victory. Celta came into the game unbeaten in six matches in all competitions.
Sevilla continued their prolific run of form at home after beating Espanyol 2-0 at the Sanchez Pizjuan with goals from Ciro Immobile and Ever Banega - their seventh consecutive league win.
A late goal by Duda saw Malaga beat Levante 1-0 to pick up a third straight league success and leave their opponents rooted to the bottom of the table, while goalkeeper German Lux helped Deportivo earn a goalless draw at Getafe to preserve their 10-game unbeaten run in all competitions.
Second-half goals from Sergio Keko and Gonzalez Borja Baston saw Eibar earn a 2-0 win against Sporting Gijon which halted a five-match winless run.
And Las Palmas returned to winning ways as they claimed a much-needed 4-1 victory over fellow strugglers Granada, with Pedro Dominguez, Sergio Araujo, Jonathan Viera and a David Lomban own goal securing the win.