Italian midfielder Massimo Donati completed his move to Serie A club Bari from Celtic on Monday.
Donati has returned to Italy after two years with the Scottish Premier League team.
The 28-year-old made it clear he wanted to quit Celtic last season following a frustrating spell out of the team during Gordon Strachan’s reign.
Although Donati had been more involved since the arrival of new manager Tony Mowbray, he was still keen to go back to Italy for family reasons.
“I asked Celtic for the chance to return to Italy and I am very grateful for granting me that wish,” Donati told Celtic’s website.
“The new manager at Celtic trusted me and respected me but my desire to return to Italy was too strong.
“I’ll miss playing in Scotland. The league is more physical and the Italian league is obviously more technical.
“But what I will miss most of all is the fantastic supporters and the atmosphere they create at games. We can learn a lot from them in Italy.”
Donati joined Celtic in June 2007 from AC Milan and made 54 appearances for the Hoops.