Barcelona have taken a big step towards a third successive league title as Pique's 67th minute strike gave the Blaugrana a precious win at El Madrigal.
A solitary goal from Gerard Pique was the difference as an under-strength Barcelona edged a narrow game against Villarreal to win 1-0, and pull eight points clear of Real Madrid in the title race.
Neither team ventured forward with great purpose nor determination in a bland opening 45 minutes. The impetus surely should’ve been with Barcelona as the shock result of Madrid's defeat meant a win for Guardiola's men would've put them eight points clear of Los Merengues.
However Giuseppe Rossi came close to breaking the deadlock in the 5th minute. Victor Valdes reacted brilliantly to smother the ball from the lurking Italian who showed uncharacteristic hesitancy in front of goal.
The diminutive ex-Manchester United man was again denied by Valdes. Latching onto a sumptuously weighed through ball from Santi Cazorla, his thumped effort was punched away by the 'keeper with Marco Ruben missing out on the rebound by a matter of inches.
The Catalans passed the ball around with no great urgency, clearly missing the highly influential pairing of Lionel Messi, who was on the bench, and Xavi who was serving a suspension. The home side threatened sparsely with Cazorla and Rossi providing the Barca defense with some spasmodically uneasy moments.
Just before the interval, the Blaugrana reminded their hosts of the danger they pose. David Villa latched onto a loose ball but Catala managed to put it behind for a corner. From the resulting set-piece, Spain's record goalscorer followed up only to see his tame effort drift wide.
The second half continued in the same uninspiring manner and Guardiola had enough. Messi was brought on in the hope some energetic play would be injected into a so far lethargic attack.
However if anything, Villarreal became more adventurous in their attacking, with Barca seemingly content to pass the ball around without carving up any openings. Then suddenly Messi and Afellay upped the tempo and their combination soon inspired a break through.
A corner flicked on by Sergio Busquets was controlled majestically by Gerard Pique on his chest and he slammed it into the top left corner emphatically to give his team the advantage at last.
Alves could've helped double the lead minutes later, but his cross was too high for Afellay as Barca looked to push home with the win.
Messi was now beginning to light up the game and the Argentine was denied by Diego Lopez, the Argentine seeing his effort tipped away from goal. Valdes was to make the save of the game, though, as a swift counter from the hosts nearly conjured up an equalizer. Nilmar was somehow denied by the Spanish keeper's sprawling legs and the lead remained intact.
With the hard-fought victory at El Madrigal, Barca extended their lead at the top of La Liga to eight points. Meanwhile, Villarreal fall to fourth, three points behind Valencia in the race for automatic Champions League qualification.