Ernesto Valverde concedes there is room for improvement despite watching his Barcelona side beat Real Sociedad 2-1 on Saturday to maintain their perfect start to the season. 

The Catalan giants fell behind to Aritz Elustondo's fine early finish and were only spared going further behind thanks to some profligate finishing from the hosts. 

Luis Suarez took advantage of those missed chances to pull Barca level in the 63rd minute before Ousmane Dembele's third of the season sealed maximum points three minutes later. 

Barca were a long way from the free-slowing side that thumped Heusca 8-2 before the international break and Valverde is well aware that there is more to come from his men. 

"These are three very good points, everything was very hard and we had to work a lot," he said.

"I'm not very worried, although there are things to improve. 

"Real Sociedad have a good team, it's not easy to win here and what we have to do is risk more. 

"These were three very complicated points and we know how difficult it is to win at this stadium, as it was last season.

"I'm not going home worried, but we'll try to correct the mistakes."

Valverde introduced Philippe Coutinho at the interval in a bid to inject life into his listless attack and goalscorer Suarez believes the Brazilian was key to the win. 

He added: "In the second half, Coutinho did very well when he came on and he was decisive in the match. He changed it."