The United States international opened the scoring for his new club against Torino during a match that they would go on to win 4-1.
Milan have certainly benefitted from Chelsea's transfer business in recent times with Olivier Giroud also scoring twice on Saturday.
And it was Ruben Loftus-Cheek, who also joined the Rossoneri from Stamford Bridge along with Pulisic, that set up his former Blues teammate.
It is the second goal the 24-year-old has scored for Milan after also netting on his debut on the opening day of the season against Bologna.
It has left many Chelsea fans in a state of disbelief after Pulisic failed to impress too often during his four years at the club - with some even comparing him to current star Mykhailo Mudryk.
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One fan said: "Selling him was stupid."
Another wrote: "Pulisic is way better than Mudryk and he cost less."
And this fan put: "Pulisic should be cooking for Chelsea. Never got a fair chance."
While another supporter tweeted: "A fit Pulisic is always better than Mudryk."
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And another ranted: "I tired telling y'all for the past two seasons. We were wasting a top player. Our system was awful for attackers.
"We bought way too many left-sided players too. Pulisic only had one injury for 6 weeks in each of the past two seasons. Wasn't given a proper chance since summer 2020."
Pulisic's second was a classic goal poacher's effort after a brilliant run from Loftus-Cheek.
The midfielder surged past a defender before cutting the ball back after the goalkeeper had come out.
It gave Pulisic an open goal, giving him a perfect start to life in Milan with two Serie A goals in two matches.
The American made the move to Italy from Chelsea for a fee that could reach £19million, representing a massive decline on the £58m they spent on him from Borussia Dortmund in 2019.
But his time at Stamford Bridge was largely hampered by injuries that meant he could not manage a consistent stretch of first-team action.