The youngster, who claims he is improving since his summer move from AZ, has urged his PSV to go all-out against the Rossoneri on Tuesday
The first leg on Tuesday at the Philips Stadion comes before Serie A has kicked off, while the Eredivisie is three rounds into the 2013-14 campaign, with the Eindhoven giants atop the table.
The 20-year-old is revelling in the opportunity to play against a club as big as the Rossoneri and has urged his teammates to go all out to knock Massimiliano Allegri's men out of the competition and make it into the group stage.
"I think it's very exciting to play against AC Milan," the 20-year-old told Goal. "We must do everything to win it. I am confident in a good result."
Maher joined PSV for an estimated 8 million euros in the summer from AZ and the midfielder believes that he is improving alongside his new teammates at the club.
"I think I'm making progress," the Dutchman added. "We feel more closely-knit in midfield and know what to expect from each other."
PSV-Milan kicks off on Tuesday ahead of the return leg at San Siro on Wednesday August 28.