Willian expects Serbia to provide Brazil with a much tougher test than their last opponents as the host nation continue their World Cup build-up in Rio on Friday.
Brazil take on Ljubinko Drulovic's side in an international friendly at the Maracana, three days after dispatching Panama 4-0.
Chelsea midfielder Willian, who scored for the five-time world champions in Tuesday's triumph, expects a different and harder challenge this time around.
He said: ``It will be much tougher, a completely different story.''
David Luiz, who recently moved to Ligue 1 champions Paris St Germain, echoed his former club team-mate's sentiments.
He said: ``It will be very useful for us, a very tough game, but we know them.''
Brazil coach Luiz Felipe Scolari plans to field a strong XI at the Maracana, which means star striker Neymar, who also netted in Tuesday's match, should feature.
Scolari said: ``I need to see the team before the (World Cup) debut (against Croatia on June 12).
``Neymar received some hard hits against Panama, but I have no reason to save him in this game.
``He wasn't playing in Barcelona due to an injury, so he need rhythm, he needs to play.''
Serbia boss Drulovic concedes that Brazil are tipped by most to win the match, but he believes his side have the ability to produce a shock result.
The head coach told Serbian broadcaster B92: ``Brazil is the favourite on paper, but I think we have a really good team.
``If we play at their level and concentrate for 90 minutes, I think we can fight for a good result.''