Fiorentina preserved their 100 per cent record in UEFA Europa League Group K with a 1-0 victory over PAOK on Thursday.
Juan Manuel Vargas was the hero for the Serie A outfit at the Stadio Toumbas, on hand to tuck away a 38th-minute rebound as Fiorentina made it three wins from three matches in Europe.
The win came less than a week after Fiorentina were disappointingly beaten 2-0 at home to Lazio and Montella hopes the Florence-based side can build on the result heading into Sunday's trip to Milan.
"The team gave a good response and I really liked the attitude," Montella told reporters.
“In Italy there is always a reason to stress out a coach, even if he's top of the table. This victory can boost enthusiasm and confidence, as happened after our win at Dinamo Minsk.
"Even towards the end when we were under pressure, we suffered all together. We were also tired, but fought hard to bring home a precious victory against our most dangerous group opponents.
"The group is still open, but we have an important advantage now and must make the most of it in the next few games."
Thursday's triumph also meant a third consecutive clean sheet, with Fiorentina yet to concede a goal in the group.
"It was a great victory and it was especially pleasing to win without conceding a goal," Fiorentina defender Micah Richards said afterwards.
"I am really happy with how we played and got the three points after losing in Serie A in our last league game."