Messi, Neymar on target as Barca hit Rayo for six
Barcelona's forward Lionel Messi celebrates his goal during a Spanish league football match against Rayo Vallecano at the Camp Nou stadium in Barcelona on February 15, 2014 - by Josep Lago
Atletico Madrid remain level on points with the Catalans as they too were 3-0 winners over Valladolid on Saturday.
Adriano got Barcelona off to a flying start when he curled home the opener inside two minutes.
Lionel Messi and Pedro Rodriguez then struck the post before Messi doubled Barca's lead before half-time with a delightful lob over Ruben Martinez.
The Argentine then teed up Alexis Sanchez to make it three before Pedro rounded off a wonderful team move involving Andres Iniesta and Cesc Fabregas.
Messi got his second of the evening midway through the second-half to overtake Real Madrid legend Alfredo di Stefano as the third-highest scorer of all-time in La Liga on 228 goals.
And Neymar rounded off a perfect evening for the hosts on his return from a sprained ankle when he blasted home the sixth from long-range two minutes from time.
Barca boss Gerardo Martino handed a rest to Xavi Hernandez, Javier Mascherano and Jordi Alba with the City clash in mind, whilst Neymar made his return from an ankle injury as he was named on the bench.
Adriano was one of those handed a start by the changes and he took just 90 seconds to make his mark with a fine strike from 25 yards.
Messi and Pedro were then unfortunate to both strike the woodwork as Barca laid seige upon the Rayo goal in the early stages.
However, Victor Valdes had to be alive to prevent the visitors levelling when he bravely parried the ball away from the feet of Alberto Bueno before blocking Iago Falque's follow-up effort.
It seemed only a matter of time before Barca found a second goal, though, and it duly arrived when Messi clipped home Fabregas' pass over the advancing Ruben.
The four-time World Player of the Year turned provider seven minutes after half-time as his through ball was dispatched by Alexis Sanchez for his 15th league goal of the season.
Barca's best was yet to come as a sensational backheel from Iniesta freed Fabregas inside the area and he unselfishly squared for Pedro to slot home from close range.
Neymar was then introduced for the first time in three weeks, but it was Messi who was next on the scoresheet as he slotted Sanchez's pass into the far corner.
Messi was then withdrawn to keep him in reserve for the Etihad on Tuesday, but Barca's hunger for goals continued and only an amazing goal line clearance from Ze Castro prevented Fabregas from adding a sixth.
There was nothing the Rayo defence could do to prevent Neymar rounding off the scoring, though, as the Brazilian fired brilliantly into the top corner from outside the area.
- Atletico get back on track -
Earlier, two goals inside the first four minutes guided Atletico to a comfortable win over Valladolid.
After three consecutive defeats in league and Cup it was imperative for Diego Simeone's men to get back to winning ways if they were to maintain their title challenge and they couldn't have made a better start.
Raul Garcia opened the scoring from a well-worked free-kick after three minutes before Diego Costa lofted in his 25th goal of the season 60 seconds later.
And Diego Godin rounded off the scoring when he headed home the third from Koke's corner 17 minutes from time.
"The key was the intensity that the players started with. Going 2-0 ahead allowed us to relax and once it went 3-0 even more so," said Simeone.
However, the Argentine continued to play down his side's chances of fighting for the title.
"We continue to go minute by minute. We are happy to be top of the league until eight o'clock this evening, but there is still 14 games to go which is a lot."