Barcelona battled to a 1-0 win over Real Valladolid on Saturday to make it two victories from two in their LaLiga title defense.
Ousmane Dembele's second-half strike settled matters at the Jose Zorrilla against last season's LaLiga123 play-off winners.
Valladolid thought they had equalised through Keko in second-half stoppage time, but the goal was ruled out for offside after a VAR referral.
It was a far from convincing display from Ernesto Valverde's side, but it means they move top of the table ahead of Sunday's fixtures, while Valladolid are still looking for their first goal and win of the season.
Barca recalled Philippe Coutinho to the starting line-up but struggled for rhythm in the first half, with Dembele wasting the best of the early chances following a fine cushioned pass from Lionel Messi.
Dembele remained the most threatening of the champions' attackers, though, and made the most of his next good chance, sending a controlled volley past former Barca goalkeeper Jordi Masip 57 minutes in after a header down from Sergi Roberto.
Valladolid responded well to the setback and looked the most likely to score next, with Marc-Andre ter Stegen saving from Keko and Kiko Olivas in the final 15 minutes.
Luis Suarez had what he thought was the decisive second goal disallowed for offside, but Barca held on to make it two wins and no goals conceded from two league games this term, although it took a VAR intervention to deny Keko's last-gasp header.