Chelsea confirmed on Wednesday that they had reached an agreement with Borussia Dortmund over a €64million transfer for the United States global.
"I didn't know anything about Pulisic yesterday", revealed Sarri.
"My opinion was positive and today I've known that the deal is done but I didn't know anything".
The signing does not seem to have helped the Blues misfiring upfront after they were held to a 0-0 draw by the Saints in a Premier League encounter.
The Ivory Coast global has attracted the attention of several clubs in Europe with his performances for the Rossoneri and some of them are keen to snare him away from the San Siro. Their next Premier League match sees them host Newcastle on Saturday, January 12. "I think we need something else for our characteristics", Sarri said when asked if he would consider recalling on-loan forwards Michy Batshuayi and Tammy Abraham.
"I have to try to improve my players, my team, my offensive base. For taking players in the academy, we are really very lucky, or the academy is very good".
"I think we played a very good match for 80 metres of the pitch, then we were in trouble for the last 20 metres", Sarri said, as quoted by Chelsea's official website.