Blues completed the permanent signing of Italian midfielder Diego Fabbrini from Premier League side Watford on 27 January, 2016.
Fabbrini joined the Club in a £1.5 million deal and on a three-and-a-half year contract, which runs until 2019.
He can play in a variety of positions across the front line and returns to Blues following a successful loan period at St. Andrew's at the end of the 2014/15 campaign.
He first joined Blues on an emergency loan in late March 2015 and went on to make five appearances, with his last start in his previous spell at the Club coming in Blues' 1-0 win away at Bolton Wanderers on the final day of the 2014/15 season.
Prior to arriving at St. Andrew's for a second time Fabbrini was on loan at Championship side Middlesbrough, where he made a total of 26 appearances and scored six goals.
A full Italian international, with one cap to his name, Fabbrini, began his career in his home country with Empoli, before joining Udinese and then making the switch to Watford in 2013.