Casemiro has spent the last nine years with Madrid and has a strong relationship with head coach Ancelotti.
Ronald Koeman’s final game was the 1-0 defeat by Rayo Vallecano in La Liga on Wednesday night.
The four-time winner of African Player further pledged to introduce radical changes in Cameroon football.
Pochettino stated that it took a while to process that the club had signed the six-time Ballon d’Or winner.
He is expected to feature when they take in a trip to Brest for their next Ligue 1 outing on August 20.
Lacazette has one year remaining on his Emirates Stadium contract and is apparently open to joining Barca.
Barcelona are reportedly on the brink of confirming a new two-year contract for Lionel Messi.
Ronaldo has already scored three goals for Portugal at this year’s Euro 2020 tournament.
PSG president Nasser Al-Khelaifi has confirmed that Barcelona tried “very hard” to re-sign Brazilian attacker Neymar.
City’s record goalscorer announced earlier this season that he will leave the club when his contract expires in the summer.