Balotelli leads Milan to win in debut
All eyes were on the mercurial Italy striker following his £19million return to Italy and it took him only 24 minutes to open his account in Rossonero colors, even if the goal could have arrived much sooner.
Udinese made the most of the hysteria to spring a surprise at the San Siro in the second half, Gianpiero Pinzi souring the party atmosphere with a goal on the counter-attack.
Balotelli's head appeared to drop as Milan drifted towards a draw but he snatched up the ball with glee when Stephan El Shaarawy won a dubious penalty from Thomas Heurtaux.
The former Inter Milan striker did not miss from the spot and Udinese were left protesting the perceived injustice as Milan celebrated reaching fourth place.
There was a heightened air of expectancy in a crowd who unfurled hundreds of banners to welcome their hero home before the teamsheet had even been released.
And so there was tangible disappointment when Balotelli's name was only listed among the substitutes, with Giampaolo Pazzini preferred alongside M'Baye Niang and El Shaarawy.
But soon fate intervened as Pazzini injured himself in the warm-up. Balotelli took to the field from the start and almost scored inside 35 seconds.
The 22-year-old ploughed through the Udinese midfield to drag a daisy-cutter just inches wide of a post. He soon put Niang through on goal with a tricky reverse pass but Daniele Padelli repelled the threat with an outstretched boot.
Udinese were not in town as part of the welcoming committee and Luis Muriel soon made his side's intentions clear with a fine run and finish that might have been better converted had he passed to Pinzi.
El Shaarawy reminded the home fans of what he could do with a near miss from a header but the stage had always been set for the new arrival.
A typically muted celebration greeted rapturous applause as Balotelli hooked El Shaarawy's pullback from the by-line underneath Padelli and into the back of the net.
He nearly found a second in style, Padelli racing back to flap his long-range drive out of the far corner.
Dusan Basta did his best to surprise Milan keeper Marco Amelia on the counter-attack, to no avail, before Padelli survived yet another scare as Mathieu Flamini came up short on a square ball from El Shaarawy.
Milan had dominated the first half and they continued to channel their play through their new icon after the break.
A near-miss from Antonio Di Natale failed to inspire the necessary caution, though, and Udinese caught their hosts napping in the 55th minute.
The sprightly Muriel raced clear of the offside trap to drag Cristian Zapata out of position, with Pinzi left all on his own to slip the ball over Amelia and into an empty net.
Balotelli did warm Padelli's palms soon after, but he shrugged his shoulders after missing an easy chance to tuck home a Kevin Constant cross.
Niang tried to force the issue but slammed the ball wide of a post because Udinese had done enough to narrow the angle.
A spell of heavy Milan pressure found Niang with the goal at his mercy but instead the young Frenchman rattled the crossbar with a furious drive.
El Shaarawy was barely touched as he tumbled in the box under the attentions of Heurtaux, with Balotelli unmoved by any protests as he beat Padelli with a dummied penalty, the last kick of the match.