PiqueÃ¢â‚¬â„¢s attempted clearance of Javier CamunasÃ¢â‚¬â„¢ by-line cross flew into the net after striking helpless goalkeeper Valdes in the face and forced Barcelona to settle for a draw that saw their lead ahead of Real Madrid at the top of La Liga cut to just one point.
Prior to the goal, Seydou Keita maintained his impressive scoring streak by completing the easiest of finishes after Carlos PuyolÃ¢â‚¬â„¢s cut back to give his side a deserved lead with only a quarter of the game remaining.
The match began at a frenetic tempo and Barca almost grabbed the lead through Lionel Messi as early as the first minute.
The majestic Argentine cut in from the right to curl a shot towards the top left corner that required Osasuna goalkeeper Ricardo to tip the ball over at full stretch.
Barcelona received a let-off on 12 minutes after Carlos Aranda appeared to break the offside trap after being sent clear on goal, but was denied by the assistant refereeÃ¢â‚¬â„¢s flag despite being played a yard onside by the deep-lying Eric Abidal.
Keita was clearly in a confident mood in front of goal following last weekÃ¢â‚¬â„¢s hat-trick against Zaragoza as he struck a venomous half-volley wide from 20 yards.
Minutes later, Aranda was justly cautioned after attempting to deceive the referee into awarding his side a penalty with a disgraceful dive inside the area with both Pique and Dmytro Chygryinskiy in close proximity.
Osasuna were enjoying a highly competitive first quarter of the game in front of a raucous crowd in the steeped stands of the Estadio Reyno de Navarra and created more panic inside the Barcelona 18-yard box on 21 minutes.
Francisco Juanfran Ã¢â‚¬â€œ a product of the Real Madrid youth academy Ã¢â‚¬â€œ skipped past Chygrynskiy before pulling a dangerous ball across the six-yard box that could only be hurriedly hooked over the bar by the Barca backline.
Barca began to gain control of possession, as they so often do, and came close to taking the lead just short of the half-hour mark.
A cleverly-worked corner-kick played into the path of Zlatan Ibrahimovic by Xavi allowed the Swedish superstar time to strike at goal from 16 yards. The ball rebounded off an Osasuna defender and almost fell to Puyol he was loitering in the goalmouth.
Osasuna Ã¢â‚¬â€œ who incredibly beat both Barcelona and Real Madrid in the final two games of last season to stay in the Primera Liga Ã¢â‚¬â€œ struggled to cope with BarcelonaÃ¢â‚¬â„¢s ability to retain possession and their dominance continued well into the second-half.
The home side were lucky not to have been reduced to 10 men after Ibrahimovic was brought down when he was clear on goal by Miguel Flano after the defender, who was the last man, mis-controlled the ball at the halfway line, but the incident Ã¢â‚¬â€œ to the irate reactions of the Barcelona players Ã¢â‚¬â€œ went unnoticed by the referee.
Their frustration was eased after Keita sent the Catalan club into the lead on 72 minutes.
Several probing passes around the Osasuna 18-yard box resulted in Messi sliding Puyol in on his right and the captain sent the ball back across goal for Keita to control and prod home from two yards for his sixth goal of the season.
Puyol himself had an opportunity to double his sideÃ¢â‚¬â„¢s lead on 84 minutes but failed Ã¢â‚¬â€œ rather predictably Ã¢â‚¬â€œ to keep his curling left-foot effort down from all of 20 yards.
Messi thought he had sealed the result in the second minute of stoppage-time after being fed in on goal from a free-kick, but uncharacteristically failed to slide the ball left-footed either side of Ricardo and the former Manchester United goalkeeper was able to block the shot.
It proved to be a pivotal moment of the match as Camunas took full advantage of an error by second-half substitute Rafael Marquez to cross the ball in from the by-line where Pique and Valdes unwillingly diverted the ball into their own net.
Osasuna: Ricardo, Azpilicueta, Flano, Josetxo, Monreal, Juanfran (Galan, 83), Punal (Ruper, 78), Nekounam, Camunas, Pandiani, Aranda (Shojaei, 71)
Barcelona: Valdes, Puyol, Pique, Chygryskiy (Marquez, 61), Abidal, Busquets, Xavi, Keita, Iniesta (Pedro, 90), Ibrahimovic, Messi
Man of the Match: Seydou Keita Ã¢â‚¬â€œ He continued his impressive contribution of goals from midfield and was unfortunate not to have been the match-winner.
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