Milan replaced Gennaro Gattuso with former Sampdoria coach Giampaolo during the close season in a bid to improve on last season's fifth place and to take them back to the Champions League.
The Portuguese forward then fired in the penalty in the sixth minute of stoppage time.
Anger driving City to new heights, says City manager Manuel Pellegrini.
Pep Guardiola drew first blood in his renewed managerial duel with Jose Mourinho as Manchester City deservedly won an absorbing Premier League derby 2-1 against Manchester United at Old Trafford on Saturday.
Check out the top footballers of the weekend...
Manchester United were denied by a spirited Stoke City performance as Joe Allen pounced late to secure the visitors their first point at Old Trafford since 1989 in a deserved 1-1 Premier League draw.
News of all that's transpired on and off the football field
Serie A witnessed some breath-taking football action, especially when AC Milan could not convert the umpteen chances they had against Sassuolo while Inter went to top. In Ligue 1 action, all the star players found the net for PSG. Here are images from the soccer matches played across Europe on Sunday.
News of all that's transpired on and off the football field
IMAGES from the Champions League matches played on Tuesday
After Sunday's crushing 4-2 derby defeat at Manchester United, even a top four finish and a place in next season's Champions League is no longer a certainty.
Everyone at Manchester City is flying high after the 1-0 derby win over Manchester United at the weekend but they could all come crashing back to earth after Wednesday's meeting with CSKA Moscow in the Champions League.
Manchester City suffered a shock League Cup defeat at the hands of a reinvigorated Newcastle United, who reached the quarter-finals with a superb 2-0 away win on Wednesday that left the holders nursing the wounds of a bruising past eight days.
News of all that's transpired on and off the football field
Leicester City continued to do their best Houdini impression on Saturday as they escaped the Premier League drop zone for the first time since November while Manchester City went up to second spot with a thrilling win.
Queens Park Rangers bowed out of the Premier League with a whimper after Manchester City's Sergio Aguero scored a hat-trick to lead his side to a crushing 6-0 victory over the London club on Sunday.
Barcelona battled back from a goal down and scored twice in the second half to overcome hosts Borussia Moenchengladbach 2-1 in their Champions League Group C match on Wednesday despite the absence of the injured Lionel Messi.
Lionel Messi-inspired Barcelona overwhelmed Manchester City as Ivan Rakitic's strike secured a 1-0 win.
VfL Wolfsburg reached the Champions League last 16 and dealt a knockout blow to Manchester United with a 3-2 victory to claim top spot in Group B and condemn their opponents to the Europa League on Tuesday.
The politically-sensitive Euro 2016 qualifier between Serbia and Albania was abandoned on Tuesday following a brawl between players from both sides after a flag stunt.
Substitute Ki sung-Yueng drove in an extra-time winner to take the Premier League's bottom club Sunderland into the League Cup semi-finals with a dramatic 2-1 victory over Chelsea on Tuesday.
A summary of Wednesday's group matches in the UEFA Champions League.
News of all that's transpired on and off the football field
A goal by Sergio Aguero gave Manchester City a 1-0 victory against neighbours Manchester United, who played with 10 men for more than 50 minutes on Sunday.
Chelsea face the prospect of having veteran Didier Drogba as their only fit striker for their visit to Manchester United on Sunday in what is usually one of the standout matches of the Premier League season.
Chelsea came from behind to secure a 3-1 win at Manchester City and forge further clear at the top of the Premier League as a dramatic top-of-the-table clash ended in a mass brawl and two City players being sent off on Saturday.
Chelsea icon Frank Lampard scored for Manchester City to end his old club's perfect start to the Premier League season while Leicester City came from 3-1 down to beat Manchester United 5-3 on a remarkable day in the Premier League on Sunday.
News of all that's transpired on and off the football field
News of all that's transpired on and off the football field
Manchester City's Sergio Aguero scored a hat-trick as coach Pep Guardiola maintained his 100 per cent record at the club with a commanding 4-0 victory against Borussia Moenchengladbach in their rearranged Champions League Group C opener on Wednesday.
Photos from the Champions League matches played across Europe on Tuesday