Playing up front in our 4-2-3-1 system, Nacer fired us ahead with a beauty into the top corner from 25 yards in the eighth minute at the Allianz Arena.
We were in control from there and Tom Carroll completed a deserved win with the second goal in the 70th minute.
Early chances came and went in our opening match against Real Madrid – a 2-0 loss on Tuesday – but the result appeared in little doubt once Nacer struck.
“We started well, created chances and I scored a nice goal, it was a good start again,” said Nacer, who hit double-figures for us from midfield last season.
“AC Milan defend very deep so I shot from 25 yards and sometimes you need those actions to make a difference. It was nice to be on the scoresheet.”
Focus now turns to the real thing and the big kick-off against Manchester United in the Premier League on Saturday (12.45pm).
“Everyone is fit and we’ve worked very hard in pre-season to be ready for this game,” added Nacer. “I think we’re ready and we want to show it on Saturday.”