United secured a 0-0 draw in the first leg in Italy, but Balotelli reckons the Premier League giants could be made to pay for failing to find the net.
Balotelli told Sky Sports: “In a European tie, 0-0 is not a bad score. If we score there, they will need to score two goals, which is not easy.
“It is now 55-45 for them because they are at home. They are a great team as we all found out in the first leg, however we are also very good.
“We will be ready for Old Trafford, our manager has got a great record there as well, so we will be fine, but it will be difficult.
“Hopefully our big players will do well and theirs will be off their game.”