The Ukrainian outfit became the first team to beat Manchester City this season as they clinched a 2-1 home victory in the final round of Group F matches on Wednesday evening.
Fonseca had previously promised to don a full Zorro outfit should his side reach the knockout rounds, something they achieved this week.
"This is the most joyful press conference of my career," he said.
“We played an almost ideal game. We were very disciplined in defence and broke through to attack very effectively.
“It was very important to close up some particular zones for Manchester City where they are usually very dangerous.
“I think we did that well and they did not threaten as they normally would."