"Mario is an unusual boy and it is also obvious that his mind is no longer with us, nothing different from what he has always been," Massimo Cellino told Telelombardia.
"I love him, I hoped that the air of home and the desire of the national team would do him good. We are all disappointed another time".
Balotelli, who has 36 caps for Italy, joined Brescia last summer, as he targeted a return to the national side for Euro 2020, which has been postponed due to the coronavirus pandemic.
But the 29-year-old scored just five goals in 19 matches, with the Lombardy club sitting bottom of Serie A when the championship was suspended on March 9.
The former Inter Milan, Manchester City and Liverpool striker has not always been present at training since it resumed in Italy on May 4.