Gimenez struck in victory at Empoli - becoming the first Mexican to do so for the Rossonero.
He later said, "I'm very happy, it was a difficult match but we came in well and made the difference.
"Against Feyenoord it will be a tough match, but also full of emotions for me."
Milan meet Gimenez's former club Feyenoord in their Champions League round 16 playoff this week.