Milan - Alessio Romagnoli scored the only goal after 97 minutes as AC Milan reclaimed fourth place in Serie A amid drama at 10-man Udinese on Sunday ahead of Lazio who earlier crushed SPAL 4-1 with Ciro Immobile bagging a brace.
Defender Romagnoli fired in the winner amid a scramble in front of goal to add to his midweek winner against Genoa, for a confidence-boost ahead of next weekend's visit by champions Juventus to the San Siro.
"I know it burns to lose in the last minute," said Milan coach Gennaro Gattuso, whose side have won three league games in the past week after losing the Milan derby to Inter following a dramatic Mauro Icardi injury-time winner.
"I liked really our performance and attitude. We arrived with injuries and suffered, but deserved this victory," added Gennaro after Milan kept their first clean sheet of the campaign.
AC Milan and Lazio both have 21 points from 11 games, with Gattuso's side occupying the final Champions League spot on goal difference.
The two teams are ten points behind leaders Juventus, who continued their unbeaten run with a 3-1 win over Cagliari on Saturday.
Milan suffered an early blow Sunday when Argentine striker Gonzalo Higuain was forced off after 35 minutes with a back problem and was replaced by Samu Castillejo.
"Higuain felt a twinge in his back," said Gattuso, "but it doesn't seem to be anything serious."
Spaniard Castillejo forced a series of saves from Juan Musso, setting up Suso for what looked like a sure opener after 59 minutes only for his compatriot to fire over when alone on front of goal.
Udinese left-back Bram Nuytinck was harshly sent off in injury time for a foul on Castillejo and two minutes later Romagnoli jumped on an Nicholas Opoku blunder.
Amid a scramble in front of goal, Suso was unable to finish off so the captain fired in himself.
Despite the offside flag being raised the goal stood after consultation with the video assistant referee (VAR). It was the first game this season than Milan have not conceded a goal.
Earlier Lazio bounced back from last week's 3-0 home defeat to Inter Milan.
"We had to redeem ourselves after the knockout against Inter," said coach Simone Inzaghi, whose side are now five points ahead of city rivals Roma, who were held 1-1 by Fiorentina on Saturday.
"Today's three points are very important for us in terms of ranking. The lads remained united and compact without suffering the psychological backlash (of defeat to Inter)."
Italian international Immobile volleyed in the first after 26 minutes off a Danilo Cataldi corner, past SPAL goalkeeper Vanja Milinkovic-Savic, brother of Lazio midfielder Sergej, who was also playing at the Stadio Olimpico.
But the celebrations were short lived with Mirco Antenucci tapping in the equaliser two minutes later.
Vanja Milinkovic-Savic denied Immobile from close range and his brother Sergej Milinkovic-Savic fired over before Immobile's second.
Felipe Caicedo broke through the SPAL defence and set up Immobile, whose shot took a deflection off Filippo Costa over the SPAL goalkeeper.
Blunders by SPAL's Brazilian defender Everton Luiz allowed Cataldi and Marco Parolo to break through in the second half, but Immobile was denied a hat-trick by the woodwork.
In Genoa, Torino moved one point off the Europa League places in seventh with a 4-1 win over Sampdoria.
Andrea Belotti scored two, nodding in the first after 12 minutes and the second from the penalty spot before the break, with Iago Falque (56) and Armando Izzo (78) adding another two in the second half.
Fabio Quagliarella pulled a goal back on 65 minutes for Sampdoria who are three points off the European berths.
Sassuolo, meanwhile, inflicted a seventh consecutive defeat on tailenders Chievo with Federico Di Francesco (42) scoring and Emanuele Giaccherini turning into his own net in injury time.
Struggling Frosinone held midtable Parma to a goalless draw in a bad-tempered game in Emilia-Romagna as Atalanta came from behind to beat Bologna 2-1.