The 34-year-old struck the winning goal after 71 minutes to send the Old Lady into the quarter-finals of the competition at their Serie A rivals' expense.
"It was important to move forward [in the Europa League]," Pirlo told Mediaset after the match. "We wanted to qualify and I think it was a well deserved win from what we saw here tonight.
"A game that lasts 180 minutes [is a long time] but we knew we could do it. We want to continue progressing in Europe as well as Serie A."
Juventus currently lead the Serie A table by 14 points.