Barcelona edged to a 1-0 win over Sporting Lisbon following an own goal from Sebastian Coates at the Estadio Jose Alvalade to maintain a 100 percent start in Champions League Group D.
The La Liga leaders were left frustrated following a goalless first half as the Portuguese side produced a determined defensive display.
However, the deadlock was broken four minutes into the second half when Luis Suarez's flicked header deflected onto Coates and back into the net.
There was, though, no 100th European goal for Lionel Messi, who saw a couple of first-half chances saved and also fired over from a free kick.
It was a somewhat cagey opening, before Messi had a decent chance on 20 minutes.
The Argentina playmaker, though, shot straight at goalkeeper Rui Patricio after Suarez stepped over a pass from Jordi Alba.
The Uruguay forward then had a sight of goal himself after being played into the left side of the penalty area, but Patricio made a smart block at the near post.
Barcelona, who were 3-0 winners over Juventus a fortnight ago, kept the pressure on and Suarez teed up Messi with a lofted cross, but his header was too central to trouble Patricio.
At the other end, Barcelona goalkeeper Marc-Andre ter Stegen was finally called into action on the half-hour when getting down to stop Marcos Acuna's 18-yard drive.
On 39 minutes, Sporting forward Seydou Doumbia was shown a yellow card for diving in the Barcelona penalty area after getting ahead of Alba.
Fabio Coentrao, the defender on loan from Real Madrid, made a timely sliding block at the near post after Messi had weaved into the right side of the Sporting box.
Doumbia limped off just before half-time, replaced by Bas Dost.
Barcelona took the lead four minutes into the second half, but only thanks to a rather large slice of good fortune.
Messi floated in a deep free-kick from the right. The ball was flicked on towards the near post by Suarez, but deflected onto the chest of Uruguay defender Coates and bounced back into the net.
Sporting, who won 3-2 away at Olympiacos in their opening Group D match, went looking for an instant response, but saw penalty appeals turned away after Dost went down under pressure from Ivan Rakitic.
Messi threatened again with a break down the right, but French defender Jeremy Mathieu, who was sold by Barcelona in the summer, got across to make a recovery tackle.
It looked not to be the Argentina midfielder's night as, on 65 minutes, he curled a 25-yard free-kick over the crossbar.
With 20 minutes left, Sporting came close to an equaliser when Dost picked out Bruno Fernandes, but Ter Stegen was alert to produce a fine reaction block.
William Carvalho blasted a late chance over, but Barcelona could have added a second with five minutes left when substitute Paulinho shot straight at the keeper after being played into the Sporting penalty area.