Wenger experimented in Sunday's 2-0 Premier League win over Middlesbrough by playing Frenchman Samir Nasri in a deeper role in midfield to allow captain Fabregas to move further forward than normal.
The ploy worked as the Spaniard capped a dominant Arsenal display by scoring two goals.
"It could be that we will do it again because it was quite convincing," Wenger said in a newsletter to the club's supporters.
Fabregas recently returned after a long spell on the sidelines with a knee injury.
"Cesc gets sharper and sharper in every game," said Wenger. "He was out for three months and you don't come back to your best straight away."
The Old Trafford match will be the first European meeting between the two English clubs.
"We know each other well but still the talent on the pitch always surprises you," said Wenger. "If we play at our best we have a good chance and we can do it."
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