Messi's 27th Primera Liga goal of the season is enough to separate Barca and Valencia at Mestalla.
Barcelona remain on track as Lionel Messi rescues them again
Valencia 0 // Barcelona 1
VALENCIA // Lionel Messi's 27th Primera Liga goal of the season gave Barcelona a valuable victory over third-placed Valencia at Mestalla and saw the Catalans stretch their lead at the top to 10 points.
Messi had seen three shots kept out in one incredible move early on and missed two other good opportunities after that, but the Argentina forward was not to be denied and popped up to settle matters with 14 minutes remaining.
Barca had arguably the better chances but Valencia matched the leaders for long periods and could perhaps feel aggrieved that Jordi Alba's first-half effort was ruled out for offside.
David Villa was returning to Mestalla for the first time since his big-money summer move from Valencia, although the Spain striker arrived later than his teammates after giving evidence in a trial against his former agent in Asturias earlier in the day.
Guardiola's presence in Valencia had also been in doubt, but the Barca coach was given the all-clear to travel by club doctors, despite a lower-back problem.
Guardiola, in his third year in charge at Barca, had won at all of the other current Primera Division grounds — but never at Mestalla.
Xavi returned from injury for the match, but with Carles Puyol and Victor Valdes sidelined, the coach was forced to field an unusual line-up.
Sergio Busquets was moved into central defence to replace Puyol, while Jose Manuel Pinto took over in goal and there were also starts for Javier Mascherano and Adriano.
Messi was, as expected, heavily involved early on and missed a triple opportunity to give Barca the lead after nine minutes.
Valencia keeper Vicente Guaita somehow repelled his first two efforts with fine reaction saves, while a third was hacked clear by a teammate.
Messi also clipped a lob onto the roof of the net when he had looked certain to score after half an hour, but Barca could have been behind by then following a controversial call from the officials.
That saw Valencia's Alba ruled offside as he went clean through, took the ball past Pinto and slid into the empty net from an angle.
Replays proved inconclusive, but Valencia felt hard done by.
The home side, who had won eight of their last 10 Primera Division games, were matching Barca and substitute Roberto Soldado missed a good chance to give them the lead early in the second half, when he dragged an angled shot wide of the target.
Pablo Hernandez then fired just past the post following a quick Valencia counter-attack. The midfielder opted to shoot, but appeared to be caught in two minds and perhaps would have been better off squaring for the unmarked Soldado at the far post.
Messi then missed another great chance for Barca as he slid just wide, but the forward netted what proved to be the winner with 14 minutes remaining.
Iniesta fed Adriano on the left flank and the Brazilian sidestepped his marker before sending in an inviting low cross for Messi, who beat Guaita - who got a touch - with a low finish just inside the keeper's right-hand post.
Real can trim the gap at the top to seven with a win at Malaga tonight, when the Andalusian club's coach Manuel Pellegrini returns to the Bernabeu to face the man who replaced him at Real at the end of last season, Jose Mourinho.
Another of Pellegrini's former clubs, Villarreal, breathed life into their bid for a place in next season's Champions League when Giuseppe Rossi struck to give them a 1-0 home win over promoted Hercules earlier last night.
The Italy forward sped on to Cani's through ball in the 21st minute at the Madrigal and finished past Juan Calatayud to lift Villarreal to 50 points from 26 matches, one behind Valencia.
Juan Carlos Garrido's Villarreal side, who are still alive in the Europa League, had lost two and drawn two of their last four league matches.
Europa League champions Atletico Madrid and Athletic Bilbao stumbled in their campaigns for a European berth.
Atletico, who have won only two and lost five of their 10 league matches this year, were held to a 1-1 draw at city rivals Getafe and Bilbao squandered the lead to lose 2-1 at Real Zaragoza.
Atletico are eighth on 35 points, three behind Bilbao and Seville, who beat visiting Sporting Gijón 3-0 on Tuesday.
Espanyol lost 2-1 at home to Real Mallorca on Tuesday and remain fifth on 40 points.
In other matches last night, Osasuna drew 0-0 with visiting Deportivo Coruna and Real Sociedad and Levante drew 1-1 in San Sebastian.