Messi makes it 50 in win

Villa slid in the opener from close range before half-time, his first goal since February, while Messi came off the bench to finish inside the box and continue an astonishing season of football for the Argentine.

The win re-extends the gap at the top of La Liga to eight points. Earlier Real Madrid had hammered Valencia 6-3 at the Mestalla in a statement of intent in the title race, but Barca responded with enough to edge closer to retaining their crown.

There was a buoyant atmosphere inside the Catalan cathedral despite the sapping midweek Copa del Rey final loss to Real Madrid.

With the third Clasico of this historic quadruple coming up on Wednesday - the Champions League semi-final first leg in the Bernabeu - Pep Guardiola rested stars Messi, Xavi, Andres Iniesta, Pedro, Carles Puyol and Gerard Pique.

And the lack of star quality showed, with Barca struggling to break down their opponents and not dominating possession to the level now expected of them.

Villa looked lively in attack but was far from ably supported by Ibrahim Afellay. Jeffren played better than the Dutchman and provided Villa with his goal on 24 minutes with a low swept pass across the goalmouth from the left. It was his first since a strike against Mallorca on February 26.

Soon after Javad Nekounam bent a free-kick just wide of the top corner while Osasuna also went close when Krisztian Vadocz, left all alone in the box, headed straight at Victor Valdes.

However their best chance fell to Damia on the stroke of half-time: Kike Sola flicked across the six-yard box and the attacker's stab for goal was kneed on to the post and out for a corner by Valdes.

Iniesta appeared for Jeffren at the break but could not bring the total control usually so evident in Barca's game until the appearance of Xavi for the injured Gabriel Milito on 66 minutes.

Messi was already on the pitch, replacing Villa, but not all that involved after an immediate exchange with Alves almost saw him bearing down on goal.

There were nervous moments at the back for the champions but they began to pass the ball with more fluidity and Iniesta came close to doubling the lead when he fired a controlled, powerful shot just over first-time from an Alves pull-back.

Former Birmingham striker Walter 'El Rifle' Pandiani made an appearance for Osasuna but did not have much chance to cause problems before Messi made sure of the points in the 88th minute. Alves played him in and Ricardo could not keep out the low finish, which went under his body.

It was Messi's 31st in La Liga in 2010-11, putting him two ahead of Real Madrid's Cristiano Ronaldo in the race for the Pichichi.

The history books will show this to be the game when the Argentine etched his name still further into football folklore by bagging his 50th in a season in all competitions - but it was a difficult one for a Barca team still smarting from their loss in Valencia and with more than one eye on a huge European clash in the coming two midweeks.