The referee for Tuesday night’s Checkatrade Trophy game against local rivals Colchester United will be Stuart Attwell.
Attwell has refereed in four Premier League games this season and three Championship games, his most recent being Brentford’s 3-1 win over Leeds United on Saturday.
He has dished out 30 yellow cards in his nine games so far and one red, which went to Andy Carroll in West Ham’s 1-1 draw at Burnley a few weeks ago.
His other games came in the Carabao Cup between Leicester and Liverpool and Accrington Stanley's EFL Trophy game at home to Blackpool.
Attwell’s last visit to Roots Hall, and indeed his last Blues game, was the 3-1 win over Sheffield United in 2016.