Date of birth
Jason McCarthy became Neil Harris' seventh summer signing ahead of the 2019/20 season, when he made the move to The Den in late July 2019.
The right-back joined from Wycombe Wanderers for an undisclosed fee, on a long-term contract.
A trainee at Southampton, Jason spent time on loan at Wycombe and Walsall - playing a full season and scoring five times at the latter - before joining Barnsley in the summer of 2017.
The defender was in the side that defeated The Lions 3-1 at The Den, with Tom Bradshaw netting twice, going to make 24 appearances for The Reds before Wanderers reacquired his services in August 2018.
Jason was a near ever-present in League One in 2018/19, playing 44 times and finding the net twice, earning the Supporters' Player of the Year crown in the process.
Known for having a new-found speciality from free-kicks, Jason arrives in SE16 to provide competition in the defensive ranks.
The defender has re-joined Wycombe Wanderers on loan until the end of the 2019/20 season.