Roma eased the pressure on coach Claudio Ranieri with a last-gasp 1-0 victory over reigning Serie A champions Inter Milan at the Stadio Olimpico.
The capital club came into this match with an unwanted return of just two points from a possible 12 at the start of the new campaign but secured an overdue win thanks to substitute Mirko Vucinic's last-minute strike.
The defeat was Inter's first in the league under Rafael Benitez and leaves the Nerazzurri with a one-point lead over second-placed Chievo, who can move to the summit with victory over Lazio on Sunday.
A goal from Zlatan Ibrahimovic early in the second half was enough to earn AC Milan all three points with a 1-0 win against Genoa.
The Swedish striker struck in the 49th minute to decide a tight Serie A encounter at the San Siro.
Genoa hit the post in the first half and can consider themselves unfortunate to lose to a goal which was the result of a defensive error, but they remain with just five points from five games while the Rossoneri move up to fourth with eight points.
Milan started for the first time this season with their new three-pronged attack of Ronaldinho, Robinho and Ibrahimovic.