In a rare early kick-off at the Nou Camp, Alexis Sanchez opened the scoring with his first goal of the season after less than six minutes and Lionel Messi celebrated putting pen to paper on his two-year contract extension earlier this week by notching - for the 13th straight game in La Liga - on 13 minutes.
David Villa's neat finish made it 3-0 in the 57th minute and substitute Cristian Tello added another 11 minutes from time.
Getafe substitute Alvaro Vazquez then grabbed a consolation for the visitors but there was still time for Andres Iniesta and Gerard Pique to add further gloss to the scoreline for the hosts.
First half strikes from Alhassane Bangouraan and Leo Baptistao saw Rayo Vallecano to victory in the Madrid derby over Atletico.
Second-placed Atletico - who had lost just one of their last 10 - were never in the game with Radamel Falcao's last-gasp strike a mere consolation, while defensively their inability to stop and defend crosses into the box was their downfall.
In contrast, Rayo defended bravely and showed why they are so imperious at home, with an impressive attacking display to register their fifth victory in their last six matches at the Estadio Teresa Rivero.
Real Sociedad boosted their push for a Europa League place as goals from Antoine Griezmann and Imanol Agirretxe saw off Real Zaragoza 2-1.
Zaragoza left-back Hector endured a nightmare league debut, sent off for two bookable offences after only 22 minutes to deal his team, already a goal down, a blow from which they would not recover.
Griezmann had opened the scoring after 11 minutes and Agirretxe doubled it shortly after the hour mark, with Zaragoza made to wait until deep in injury time for Apono to get their goal from the penalty spot.
Espanyol climbed above Athletic Bilbao as they capitalised on a miserable day for the Basque side with a surprise 4-0 away win.
Athletic had plenty of chances and possession but no luck and Espanyol took full advantage with goals from Hector Moreno, Victor Sanchez, Christian Stuani and Joan Verdu, the latter following up on his own missed penalty.
Victor Alvarez set up the second and third goals within seconds of each other, and only moments after coming on as a substitute, and then won the penalty from which Verdu scored.
On Saturday, Cristiano Ronaldo fired an ominous warning to former club Manchester United with a hat-trick as Real Madrid romped to a 4-1 win over Sevilla at the Bernabeu.
Matches against Sevilla have proved rich pickings for Ronaldo and it was no different on Saturday as he followed up Karim Benzema's 18th-minute opener with goals in the 26th, 46th and 59th minutes as Madrid sauntered to victory.
That took his tally of hat-tricks for the Spanish giants to an incredible 20 before he was replaced in the 63rd minute as Jose Mourinho opted to wrap his trump card in cotton wool ahead of Wednesday's visit of United in the first leg of the Champions League last-16 clash.
Granada, who stunned Mourinho's men last weekend with a 1-0 win courtesy of a Ronaldo own goal, continued where they left off against the champions on Saturday evening as they trounced Deportivo La Coruna 3-0 at the Riazor.
Carlos Marchena's own goal on the stroke of half-time set the visitors on their way and Ighalo's strike six minutes after the restart doubled their advantage.
Depor then missed a number of chances to get themselves back into the game and their night was summed up when they conceded a dubious penalty - converted by Guilherme Siqueira - in the last minute and saw Manuel Pablo sent off.
A last-gasp goal by substitute Nelson Valdez clinched a 1-0 win for Valencia against Celta Vigo at Balaidos, providing Ernesto Valverde's side with the perfect springboard ahead of Tuesday's Champions League clash with Paris St Germain.
Isco scored twice as Malaga moved back into fourth place thanks to a 2-1 win at fellow European hopefuls Levante.
Jose Barkero put the home side in front with a 27th-minute penalty, but Isco restored parity through a spot-kick in the 37th minute and then sealed the points with a neat finish just after the restart.
Finally, a stoppage-time equaliser by Pedro Geromel earned Real Mallorca a 1-1 home draw against Osasuna.
Lolo had put the visitors ahead 15 minutes from time at the Iberostar Stadium and looked to have handed Gregorio Manzano the worst possible start to his third spell in charge of Mallorca until Geromel's late intervention.
In Monday's only clash, Real Betis entertain Real Valladolid at the Estadio Benito Villamarin looking to end a three-game winless run in the league.
Sunday's La Liga Results
Saturday's La Liga Results
Monday's La Liga Fixtures