Lionel Messi will have to wait for his 100th goal in Europe after Barcelona eked out a 1-0 win at Sporting Lisbon thanks to an own-goal in the Champions League on Wednesday.
Center back Sebastian Coates was the unlucky scorer when Messi's free kick deflected off another Sporting defender and Barcelona's Luis Suarez. The ball then hit Coates and bounced into the net four minutes after halftime.
"We ended up losing to a freak own-goal," Sporting coach Jorge Jesus said.
Barcelona offered little else in attack, other than a couple of shots each by Messi and Suarez, and needed goalkeeper Marc-Andre ter Stegen to ensure the points with a key save as Sporting hemmed the visitors into their area.
The ugly slog of a match was interrupted in the 90th minute when a fan invaded the pitch to approach Messi, before being escorted off.
"We knew that to get a win here we would have to dig in.The stadium has a great atmosphere and the adversary was very strong," said Barcelona coach Ernesto Valverde, whose first season in charge has produced an eight-match winning streak and first place in both the Spanish league and the Champions League group.
Barcelona took the lead in Group D with six points from two matches after beating Juventus 3-0 in their group opener. Juventus and Sporting have three points. Juventus beat Greek side Olympiakos 2-0 in the group's other game Wednesday, with Gonzalo Higuain and Mario Mandzukic scoring for last year's finalist.
The match at Jose Alvalade Stadium was that rarest of wins for Barcelona, one that depended more on its defense anchored by the solid Ter Stegen than its vaunted attack.
Newcomer Nelson Semedo continued to impress on Barcelona's right side, and Samuel Umtiti has consolidated himself as Gerard Pique's partner in the center of the back line. The only trouble spot was on the left, where Jordi Alba had trouble keeping the speedy Gelson Martins in check, but his fellow defenders were there to cover.
Limited to a long-range attempt by Cristiano Puccini and the crosses of Martins, Sporting's Seydou Doumbia tried to draw a foul on the edge of the area when he went down after contact with Pique. The referee booked the striker, who also injured his left leg as he fell. Doumbia was replaced not long after by Bas Dost just before halftime.
Barcelona broke through after Sporting's Marcos Acuna earned a yellow card for fouling Semedo on the right side of the area. Messi crossed the resulting free kick into the packed area, where it was grazed by a Sporting player before ricocheted off Suarez and Coates.
"It was a very good free kick by Messi," Valverde said. "It was touched and we know what can happen when the ball gets into the area."
After Messi and Suarez both threatened again, Sporting had its best moments of the game.
The hoem side went close to an equalizer in the 71st when Dost deftly let a pass run through to the unmarked Bruno Fernandes, only for Ter Stegen to save his shot.
Barcelona substitute Paulinho had a great opportunity to seal the win late, but goalkeeper Rui Patricio denied him in a one-on-one.
Messi, who is on a scoring run this season with 12 goals, was left on 99 career goals for Barcelona in European competitions. The Argentina star has scored 96 in the Champions League.