Sulley Muntari and Wesley Sneijder were on target to give Inter Milan a 2-1 win over Catania at the San Siro and send the Nerazzurri back to the top of Serie A.
Ghana midfielder Muntari put the champions in front on 13 minutes when his lob into the box towards Samuel Eto'o was allowed to bounce into goal as Catania keeper Andrea Campagnolo stood motionless.
Dutchman Sneijder curled in a splendid right-footed free-kick to double the lead just past the half hour mark shortly after Patrick Vieira had thrashed the ball against the bar from short range.
Inter looked comfortable until Catania substitute Giuseppe Mascara set up a nervy finale by converting a penalty six minutes from time, given when Inter keeper Julio Cesar brought down Gianvito Plasmati after spilling a shot.
But the hosts held on for a triumph that gives them 22 points from nine games, two more than second-placed Sampdoria, who had briefly occupied the top spot by thrashing 10-man Bologna 4-1 earlier on Saturday.
Samp forward Giampaolo Pazzini, wearing a face mask after breaking his nose in last weekend's 1-1 draw at Lazio, touched in to give his side an early lead before midfielder Daniele Mannini volleyed home the second in the 17th minute.
Reto Ziegler then drove in from outside the box before Mannini nodded in an Antonio Cassano cross to complete his double and make it 4-0 with just over a third of the match played.
Substitute Pablo Osvaldo took advantage of some poor defending in the second half to pull one back for struggling Bologna, who had had striker Marco Di Vaio sent off for dissent after going 3-0 down in their first match under new coach Franco Colomba.