The Red Devils once again failed to score in a preseason friendly in Gothenburg as they slumped to defeat in a shootout with the Liga giant.
Both teams fielded strong lineups in the showpiece friendly which sold out in 45 minutes, saw the ball arrive on the pitch by helicopter and featured a firework display after the final whistle.
Perhaps unsurprisingly it was the Spanish side who started strongly, characteristically dominating possession and enjoying the best chances of an entertaining first half.
Indeed it took less than a minute for Barcelona to get sight of goal, Iniesta firing goalward but his shot was easily saved by David de Gea, returning to the United team after his Olympic efforts.
Minutes later and the Spaniard was at it again, dinking a delightful ball over the United defense and into the area for Messi. De Gea came flying out of his goal but could only flap at the ball, but fortunately for the Red Devils it skipped out of play before Messi could tap it into the empty goal.
As the half wore on, Barcelona began to profit down the United right, with Tello exploiting Antonio Valencia at right back and frequently finding acres of space but unable to pick out teammates in the box.
The Red Devils, meanwhile, were reduced to half chances. Indeed a Rooney header that flew wide and a low shot from Nani that flew past the post after a gorgeous cross-field pass by Scholes were all they had to show for their efforts in the first half an hour.
With time running out it was a late challenge that almost gave United an undeserved lead. Cristian Tello upending Nani in the penalty area, leaving the referee to point to the spot with just a minute left in the opening 45 minutes.
Up stepped Rooney but his poor effort was easily saved by Victor Valdes, who parried the ball straight back to the England international who put the rebound wide as the game went into halftime goalless.
Substitute Shinji Kagawa almost made an instant impact, a good lay-off from Welbeck allowed the Japan international to shoot low and force Pinto into a diving save, as he tipped his fizzing effort around the post.
Further changes followed with Dimitar Berbatov and Nick Powell introduced by Sir Alex Ferguson who looked visibly frustrated on the touchline; irritation which only grew after Busquets pulled back Nani on a United break, only for the Portuguese international to kick out and force the referee to book both men.
Yet despite the attacking talent on view, there was to be no breakthrough, with the crowd treated to a penalty shootout after the 90 minutes ended goalless.
First up was Nani, but after a stuttering run up his effort rebounded off the crossbar and away to safety. Xavi then slotted home coolly for Barcelona before Ashley Young also missed for United, leaving Gerard Pique to roll home the ball for the winning goal.