A last minute Jordi Alba goal was enough to give Barcelona a 2-1 win over Celtic at Camp Nou.
With Tito Vilanova's men looking to maintain their 100 per cent record in the Champions League this season, it was perhaps no surprise that they dominated possession in the early stages.
Xavi, Andres Iniesta and Lionel Messi were inevitably teaming up well, but it was Alexis Sanchez who had the first excellent chance for the Blaugrana inside two minutes. A through ball from Xavi found the Chile international, but his shot went just wide of the right-hand post.
The home team continued to have a near monopoly of the ball, as Celtic looked to soak up the pressure and hit the Camp Nou club on the break.
And that's exactly what happened on 18 minutes. Scott Brown won a free kick on the right-hand touchline, Charlie Mulgrew' whipped a delightful ball in and Samaras headed in from eight yards.
Barca remained entirely in control of possession, as the Hoops kept nine men behind the ball at all times. Vilanova's men though, just couldn't find a way past the resolute visitors, and it was left to a pair of Lionel Messi free kicks to provide the closest opportunities to worry Fraser Forster.
All the possession however, did pay dividends right on the stroke of half-time. A one-two between Iniesta and Xavi saw the former strike from inside the area, as his shot crept past the goalkeeper and into the bottom right-hand corner.
The second 45 saw Barcelona continue to control the ball, but still remained almost helpless in the face of a green-and-white wall.
The introduction of James Forrest gave Celtic an out-ball on the right-hand side, but very rarely did they pose any threat to Victor Valdes' goal.
Forster was certainly the busier of the two keepers, as he had to deal with efforts from Messi, Iniesta and Sanchez around the hour-mark, before somehow saving a close-range effort from the Argentina international late on.
It wasn't to be though for the SPL club, as a cross from Adriano found Alba, and the former Valencia man tapped in with the very last kick of the game to give Barcelona a 2-1 win.
Barcelona 2-1 Celtic
Scorers: Iniesta 45 (B) Alba 90 (B);Samaras 18 (C)
Barcelona: Valdes; Adriano, Mascherano, Bartra, Alba; Xavi, Song, Iniesta; Pedro (Tello 75), Messi, Sanchez (Villa 80)
Celtic: Forster; Lustig, Wilson, Ambrose, Izaguirre; Brown (Commons 63), Wanyama, Ledley, Mulgrew (Kayal 76); Samaras (Forrest 44), Hooper.
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