Juventus easily booked their ticket for the next round of the UEFA Champions League on Tuesday, beating FC Porto 1-0 in Italy in the round of 16.
And with Barcelona, 11-times champions Real Madrid and Bayern Munich all possible future opponents following Friday's quarter-final draw, Allegri has reason for concern.
The 1996 winners last reached the last eight in 2015 on their way to a 3-1 defeat by Barcelona in the final.
Italian champions Juventus eased into the Champions League quarter-finals with a routine second-leg win against Portuguese league leaders Porto.
According to ESPN Stats & Information, only two teams in Champions League history have won a knockout stage after losing the first leg at home.
"We have a clear idea of how we want to approach the game; we want to attack, be effective at both ends of the field and give our creative players license to influence the proceedings as best they can". If we get through we'll also be on the same level now. "So I have two questions, one at right-back and one in the middle".
Dybala, who had scored a last-gasp penalty in the thrilling win over AC Milan on the weekend, stepped up and sent Iker Casillas the wrong way in the 42nd minute to seal the deal.
Overall Porto's form is incredibly good with nine wins from their last ten matches, but their competition during this run is far lower than the standard Juventus demand of them.
The second half was played like a training session for the home side, who racked up 68% of possession and 15 shots at goal as their bid for a Champions League, Serie A and Coppa Italia treble continues. There wasn't the kind of overall ruthlessness that a lot of us were hoping to see knowing that Porto had the potential to make this a pretty interesting tie if they had gotten a goal and cut the aggregate lead in half.
Leicester's 2-1 deficit from the first leg in southern Spain was turned into a 3-2 victory on aggregate at an atmospheric King Power Stadium thanks to Wes Morgan's close-range strike in the 27th minute and Marc Albrighton's goal in the 54th.