Barca are third in the standings with three points from three games, a point behind Benfica and six adrift of group leaders Bayern Munich after being thrashed 3-0 by both teams.

They got up and running halfway through the group stage with a 1-0 home win over the Ukrainian side last month and must now claim another three points in the return match in Kyiv as they bid to finish in the top two and reach the knockout rounds.

"Barcelona have to win always. But we all know the importance of tomorrow's game," Sergi told a pre-match news conference on Monday.

"It's my obligation to squeeze the best out of my players and they have to believe they can turn things around and I see this game as a great opportunity to do it.

"They need to play with order and intensity but we should not be nervous. We play better when we are calm and composed."

The former Barca player moved up from the B team nL4N2RO47P to take charge when Ronald Koeman was sacked on Wednesday after a second consecutive LaLiga defeat - 1-0 by Rayo Vallecano.

"It’s an honour to coach Barcelona in a Champions League game. I did it as a player but it’s different. We still depend only on ourselves to go though, so we need to do our best to go back home with the win", added Sergi.

Ansu Fati, Ousmane Dembele and Frankie de Jong took part in training on Monday after coming back from injuries and will make the trip to Kyiv, though Sergi did not say if they would start.

"It’s an important game to all of us and the players need to be 100%, physically and mentally. We will see how they look on gameday and adjust," he added.

The coach also gave an update on Sergio Aguero's health. The Argentina striker was forced off in Saturday's home draw with Alaves with chest pain and is still in hospital.

"I talked to him and he's calm. He's confined to his room but considering the situation he's calm," said Sergi. (Reuters)