Milan have to attack at Old Trafford tonight - and that will give us one of two outcomes.
Sir Alex Ferguson predicts a fabulous open game.
But that will only be if the Rossoneri score first and sparkle in attack, exposing a defence that has looked shaky at times - even at Wolves on Saturday despite keeping a clean sheet.
Otherwise, United can make this a long, embarrassing night for the Italians.
It promises to be a fabulous occasion but Leonardo's decision to go for broke and pick three strikers, as is being hinted by the Milanese media, will either be a bold gamble that pays off or footballing suicide.
When Wayne Rooney headed his second goal in the San Siro, it was almost too easy.
As though age had caught up with the creaking Milan veterans and they knew it.
At that point, a humiliating defeat was on the cards.
Whether it was the introduction of Clarence Seedorf, who scored, or the respect of United is up to debate but United didn't go for the kill.
Rooney started looking for a hat-trick, unusually for him, rather than playing his usual unselfish game and chances to break away were passed up sloppily.
So Milan got a goal back and now have some hope again of progressing.
But look at the team and ask if a three-man midfield of Rene Gattuso, Andrea Pirlo and Massimo Ambrosini is going to be a match for the energy of United duo Darren Fletcher and Park Ji-sung plus the clever work of Paul Scholes.
With Nani and Antonio Valencia on the wings to ask questions of Daniele Bonera and Luca Antonini, and Rooney to worry the hell out of Alessandro Nesta, it's hard to see United not causing loads of problems for the Serie A side.
Ronaldinho is the key. He still wants to play in the World Cup and this will be the sort of stage he thrives on. If he can get on his compatriot Rafael, it will be interesting but he'll have to be back to his very best to get this side through to the quarter-finals.
Marco Borriello and Klaas-Jan Huntelaar are tipped to join him in attack with Alexandre Pato set to miss out through injury - a major blow.
Fergie says United are looking to win the game despite already holding the advantage.
It's hard to see this playing out as a dull 0-0 if Milan do change their tactics to attack the Red Devils.
And 8/11 about a home win could turn into the best bet of the week if United score first.
United are 9/5 to win at half time and full time with Victor Chandler but that's obviously riskier as Milan were the better team for the first half in Milan.
But, despite all the specials on offer, the most obvious wager could be the one here - just back United to win.
And, for man of the match, we're opting for Darren Fletcher to have another fine performance in a big game and outrunning that trio aged 30 (Pirlo), 32 (Ambrosini) and 32 (Gattuso) to get the nod at 11/1 with Blue Square.
