Willian scored in the Champions League last-16 first leg at Stamford Bridge three weeks ago before Lionel Messi scored a valuable away goal for the visitors.
Since then, Willian has netted against Manchester United and Crystal Palace to earn praise from manager Antonio Conte, who labelled the Brazilian as "fantastic" following Saturday's 2-1 victory over the Eagles.
"We have to pay special attention to him," Busquets told reporters, "but [also Alvaro] Morata, Pedro or Hazard. They have specific attack profiles. They are a good team."