The Blaugrana made hard work of Athletic Club as they eventually picked up a 1-0 win at the Camp Nou on Tuesday.
"It's not easy," Setien said afterwards.
"When there are few spaces, you have to be agile and precise.
"We've been lacking that since we returned.
"This makes it difficult, but I think we'll pick it up as the season goes on."
Ivan Rakitic came on to score the game's only goal in the second half and Setien was pleased for his midfielder.
"Today, he came on in the second half because of Sergio Busquets' card," the Barcelona boss said.
"He did well, frankly.
"He understands football very well.
"He did a good job, he won the ball back and he was involved in the decisive moment.
"I'm very happy for him.
"I understand that it's an incentive for him for the future."