Ronald Koeman believes Antoine Griezmann is growing in confidence and the Barcelona head coach hopes the forward's run of form can continue.

Griezmann scored for the third straight game for the first time in his Barca career with the opener in Wednesday's 3-0 Champions League win at Ferencvaros.

Martin Braithwaite doubled the lead before Ousmane Dembele's penalty as Barca, without the rested Lionel Messi, won their first five group stage games in a Champions League campaign for the first time since 2002-03.

But Griezmann's form is a particular boost amid the club's inconsistencies in LaLiga and Koeman praised the forward.

"It is always a matter of trust of a player. As I said many times, Antoine has always worked hard to improve his game and effectiveness for the team," he said.

"Now the goals come in and he is convinced because he has quality. I think this is important for any player.

"I hope he can continue with this effectiveness he's having lately."

After Griezmann's brilliant flicked finish for the opener, Dembele set up Braithwaite before getting on the scoresheet himself.

No player had more shots than Dembele's five and Koeman said the forward's performance would give him selection headaches.

"Dembele is a great player. He has a lot of quality, one on one, he is very fast, he is effective and manages both legs," he said.

"The most important thing is he is physically very well. He is working well.

"We know there are different players at the front and it is difficult for the manager to decide when people like Dembele are playing at this level."

Sitting seventh in LaLiga, Barca are away to Cadiz on Saturday.