Barcelona swooped to sign the 21-year-old Brazilian forward on a five-year deal from Bordeaux for an initial €41 million (A$65 million) in a surprise move after Roma had struck a deal with the French club.
"We’ve been following him for a while and [we] know him. He can definitely help the team,” Valverde said on Saturday (AEST).
“But (making the starting 11) obviously depends on a day-to-day basis and coach’s decision."
Valverde said not everyone was able to cope with the demands of playing for such a big club.
“In Barcelona we not only need to win Champions League, the demand is to win everything we play,” he added.
“Playing in Barcelona isn’t easy. The demands are really high on this club. We understand we always have to win and we also have to play well.”
With Barca playing without the likes of Lionel Messi, Luis Suarez, Ivan Rakitic, and Gerard Pique, Valverde said they might deploy different tactics as well as faces.
“We have multiple possibilities to explore regarding the system to use,” Valverde said.
“It also depends on the players you have. But we believe we can make variations, especially on defence.”
Barcelona also face Roma and AC Milan at the pre-season tournament, before facing Sevilla in the Spanish Super Cup on August 13.