Adam Barton is set to be confirmed as Pompey’s sixth summer signing.
The holding midfielder has agreed to ink a two-year deal with the Blues after leaving Coventry.
The 24-year-old made 30 appearances for the League One side last season.
Barton has a full Northern Ireland cap and has recovered from a serious leg injury suffered in 2012.
He follows attacker Adam McGurk into Fratton Park today with defender Christian Burgess’ arrival due to be confirmed tomorrow.