Real Madrid moved further ahead at the top of La Liga after they beat Real Zaragoza 3-1 and second-placed Barcelona drew on Saturday.
Real's lead has now grown to seven points following Barcelona's latest setback, with Jose Mourinho's men having won 15 of their last 16 league matches.
The 15th in that streak was at the Santiago Bernabeu where Real had to take the three points.
Lafita's goal on 12 minutes gave the bottom-placed side some hope but Kaka responded 13 minutes before half-time to level proceedings.
Cristiano Ronaldo's 24th goal of the season put Real in front just after the break and the result was secured when Mezut Oezil scored on 56 minutes.
Villarreal's form this season has been nothing short of shocking and with just one win from their last seven matches, Barcelona were expected to win easily.
But Pep Guardiola's men struggled on the road, with a goalless draw at El Madrigal making it even tougher for Barca to catch their rivals.
A Fernando Llorente hat-trick helped Athletic Bilbao to a 3-2 win at Rayo Vallecano.
Michu gave the losers an 11th-minute lead before Llorente struck on 17 and 23 minutes to give the visitors the lead.
Alejandro Arribas hit back just four minutes later in an exciting start but his goal would be in vain as Llorente scored the winner with 22 minutes to play.
Also on Saturday, Espanyol defeated a 10-man Mallorca outfit 1-0.
Manchester City loanee Vladimir Weiss scored the game's only goal after 18 minutes, with Mallorca goalkeeper Dudo Aouate given a red card just after half-time.