Roma have kept the pressure on league leaders Juventus with an outstanding run of eight successive wins that has seen them clinch second position in the table.
They have secured a berth in the group stages of next season's UEFA Champions League as a result, and although they are unlikely to catch Juve - who lead by eight points with just four matches left - Rudi Garcia has still done a tremendous job in his first campaign in charge.
Roma have lost just twice in the league this season, and beat fourth-placed Fiorentina 1-0 away last time out.
Radja Nainggolan's first-half goal was enough for the capital club, who have had 10 different players score during their winning streak.
Mattia Destro scored seven in six games before getting suspended following a 3-1 win at Cagliari earlier this month and he remains on the sidelines.
Key to Milan's run has been defensive stability, with Clarence Seedorf's side conceding just once in their winning streak.
"The whole squad is doing well and we hope to continue this run until the end of the season," Muntari told Milan Channel.
"These next two games are going to be difficult, but we can't get ahead of ourselves - we must focus first on Roma. Only after that game can we think about the derby.
"We'll go to the Olimpico and do what Mr (Clarence) Seedorf (Milan coach) tells us. Thankfully, everything is going well for us at the moment. We're going match by match."
Muntari returned from a calf injury to make an appearance off the bench in the club's 3-0 win over Livorno on Saturday.
