The Frenchman secured his spot in the final eight in a three-hour 3-6 6-7 6-7 win over Serbian Viktor Troicki earlier this week.
However, with the world number one awaiting him in the next round, Monfils admitted that he would have preferred a different opponent.
"He won 40 times but lost only once," he told reporters, when asked what to expect against Djokovic.
"It's absolutely not fun [playing against him]. It's going to be a tough match. I would have liked to be able to go further in this draw, and there would be more favourable players to play than him.
Monfils reached the final of the Legg Mason Tennis Classic in Washington earlier this month, but lost 6-4 6-4 to Radek Stephanek.