Ernesto Valverde played down Ousmane Dembele's return from a lengthy lay-off, with the Barcelona club-record signing not ready to start for the club.
Dembele made his first appearance in 110 days, coming off the bench for the last 20 minutes of Barca's 1-1 Copa del Rey draw at Celta Vigo on Thursday.
Pione Sisto cancelled out Jose Arnaiz's opener to leave the tie in the balance ahead of next Thursday's second leg, with Dembele likely to be involved again as he builds up his fitness after tearing his hamstring in September.
But Valverde — who used winger Dembele in a central striking role with Luis Suarez and Lionel Messi rested — will wait to move the 20-year-old €105 million signing into the Barca starting line-up.
"It was so that Dembele played in a position where he was released of defensive obligations, which were a bit stressful at that time of the match," Valverde said of Dembele's positional switch.
"When we know that this was the first game of this player after almost four months without playing, I preferred that he be in a position where he can gradually get used to the game.
"We must take into account that the pace of a whole match against a first division team. For Ousmane, it would have been excessive."
Barcelona have found Celta to be a bogey team of late, losing on their last two visits to Balaidos, while the La Liga game between the sides at Camp Nou last month ended 2-2.
And Denis Suarez — given a rare start in a much-changed Barca team — believes a draw is a good result to take into the second leg of the last-16 tie, with his side now unbeaten in 26 matches in all competitions.
"We have taken a step forwards this year," Suarez said. "The team is in very positive form.
"It's also positive because we have always struggled against Celta, especially away from home.
"We have an incredible squad. Whoever plays, you can't see the difference. We can get results even when the best players in the world are away."