The Brazilian opened the scoring at Old Trafford before goals from Romelu Lukaku and Jesse Lingard turned things around for United and despite Willian being on the losing side, Mourinho could not help but heap praise on the man he used to manage.
The pair worked together during Mourinho's time at Stamford Bridge and the Portuguese's respect for Willian's ability is nothing new, with Mourinho reportedly having seen an enquiry for the 29-year-old in the summer knocked back.
Speaking to 'ESPN Brazil after the game Mourinho praised Willian, even backing him to lead the 'Seleçao' to World Cup glory this summer.
"Do you want to talk about Willian? Top, cream of the crop, he’s amazing," he enthused.
"In his national team there’s no bad players. The Brazil manager (Tite) is really good with huge club experience. You guys will do great things in Russia."