Valverde: Judge us at the end of the season

The sides meet in their competition opener on Tuesday (1845 GMT) in a rematch of a quarter-final clash won 3-0 on aggregate by Juventus last season.

Barca are still coming to terms with the loss of Neymar to Paris Saint-Germain for a world record 222 million-euro fee ($267 million).

But Juventus have also seen the team that reached last season's Champions League final weakened by PSG snapping up Dani Alves and Leonardo Bonucci's move to domestic rivals AC Milan.

"They have lost Bonucci but they remain a very strong, good team," said Valverde on Monday.

"I can see the comments of comparing squads to previous seasons are the same in every country.

"People look at transfers and decide if a squad is stronger or weaker, but the time to do that is at the end of the season."

Juventus are also without the injured Giorgio Chiellini and Mario Mandzukic, but like Barca, have won all three of their league games to date this season to sit top of the table in Italy.

Despite the distraction of a chaotic summer off the field and ongoing calls for club president Josep Maria Bartomeu to step down, Barca have started La Liga in fine form.

Lionel Messi scored a hat-trick, whilst Ousmane Dembele set up a goal for Luis Suarez on his debut as Valverde's men thrashed local rivals Espanyol 5-0 on Saturday.

"It is always better to face this calibre of game after some victories with good sensations," added Valverde.

"Everyone wants to advance and have a chance of winning the Champions League.

"We are in very good form, we won 5-0, but that doesn't guarantee anything because our opponent has also started very strongly in the league."

Barca are under pressure to reassert themselves on the European stage after failing to make it beyond the quarter-finals in each of the past two seasons.

Those shortcomings have been exaggerated by rivals Real Madrid's success in becoming the first side in the Champions League era to retain the title.

"I am aware of the responsibility and I knew that when I signed," continued Valverde.

"Barca have won been champions of this competition various times in recent years."

Valverde could hand a full debut to Dembele after the 105 million-euro Frenchman only came off the bench for the final 20 minutes against Espanyol.

"He is training well, every day he is more integrated," said Valverde.

"He could start at any time, if it is not now then it will be shortly.

"The competition for places is what matters. The important thing is to win and pick the best players to do that."