Portugal midfielder Vitinha said on Saturday his talented side were full of quality but denied they were favourites for the World Cup.
Fresh from winning back-to-back Champions League titles with Paris Saint-Germain, Vitinha is joined by his club teammate Joao Neves and Manchester Unied's Bruno Fernandes in a high-octane midfield.
In attack, Cristiano Ronaldo is raring to go for his sixth World Cup and Portugal can call on younger talents Joao Felix, Pedro Neto and Rafael Leao.
"We know that we have a lot of quality and talent, with players in big clubs... but on paper, that means nothing," Vitinha said at a press conference after Portugal held their first training session at their base in Palm Beach, Florida.
"I would say we're contenders, without a doubt, we're a strong squad. But I wouldn't say that we're favourites."
Vitinha said despite a long season, he felt "very good, physically and mentally".
Portugal kick off their tournament against the Democratic Republic of Congo on Wednesday in Houston before playing Uzbekistan and Colombia in Group K.