MADRID - Barcelona moved to the top of La Liga for the first time since early November as Lionel Messi struck his 32nd hat-trick for the club in a 6-1 thrashing of 10-man Rayo Vallecano on Sunday.
Champions Atletico Madrid remain seven points off the top, though, after they were held to a 1-1 draw by Valencia at the Vicente Calderon.
Real Madrid's 1-0 defeat at Athletic Bilbao on Saturday handed Barca the chance to overtake the European champions and Luis Suarez wasted no time in taking advantage as he slotted home his sixth goal in as many games.
Gerard Pique doubled the hosts' advantage just after half-time before Messi added a third from the penalty spot at the second attempt thanks to a reprieve from the referee after his initial effort was saved by Cristian Alvarez and Tito had been sent-off for a second bookable offence.
There was no controversy over the Argentine's final two goals, though, as he moved level with Cristiano Ronaldo on 30 league goals for the season.
Both sides ended with 10 men when Dani Alves was shown a straight red card for bringing down Alberto Bueno inside the area and Bueno converted from the spot.
However, Barca had the final word when Suarez slammed home his second of the afternoon from Messi's through ball.
"The objective is to be the leader when the season ends," said Barca boss Luis Enrique.
"I have always said the big teams will lose throughout the course of the season and it will continue to happen, therefore we have to be very careful." Suarez has found his scoring touch in recent weeks after a slow start to life at the Camp Nou and was razor sharp in front of goal just six minutes in as he rolled his defender before flicking the ball past Alvarez with the outside of his right foot.
Enrique's men had to wait until after the break to make the game safe as Jordi Alba's header from Xavi's corner came back off the post and Pique was on hand to force the ball over the line.
Rayo's task became impossible seven minutes later when Suarez was pulled down by Tito inside the area and the defender was shown a second yellow card.
Messi's yips from the penalty spot continued as, after missing five of his last 10 for club and country, Alvarez comfortably saved his first effort.
However, referee Jesus Gil Manzano ruled there had been encroachment by Rayo players and gave Messi a second opportunity which he didn't pass up.
The four-time World Player of the Year was in the right place to slot home his second moments later after Alvarez had made a fine save to deny Suarez.
And Messi completed a 12-minute hat-trick with a lovely feint to leave Alvarez on the floor before rolling the ball into an empty net.
The action continued in the final quarter as Manzano levelled up the numbers by sending off Alves for a foul on Bueno inside the box nine minutes from time and the former Real Madrid midfielder converted from the spot.
However, it was Suarez who rounded off the scoring in style in stoppage time when he latched on to Messi's neat pass to round Alvarez and turn the ball home from a narrow angle.
Any chance of a title challenge to the big two has faded after the spoils were shared in the battle between third and fourth at the Calderon.
Spanish international Koke fired Atletico into the lead on his return to the starting line-up from a hamstring injury just after the half hour mark.
Tiago then missed a great chance to make it 2-0 after the break when he smashed the ball against the bar from barely three yards out.
And that miss was to prove vital as Miguel Angel Moya misjudged Dani Parejo's free-kick from the right and when the ball rebounded off the bar, Shkodran Mustafi was on hand to head home the rebound.
Elsewhere, Villarreal bounced back from their Copa del Rey elimination at the hands of Barcelona in midweek with a 4-1 win over Celta Vigo.
David Moyes's Real Sociedad also continued their march away from the relegation zone with a 1-0 win over Espanyol.