City gain revenge after cup knockout
Fifth-placed Sherwood took a third-minute lead through Liam Theakstone, but the home side fought back to equalise on 36 minutes through Dalton Stephens.
Chris Jackson put Southwell in front midway through the second half and Stephens got his second in the final minute to secure victory for mid-table City.
Sixth-placed Swanwick inflicted a rare defeat on title-chasing Hucknall Town.
Guy Taylor set the Swans on the way in the 55th minute with Ian Milson and a Henry Brooks penalty completing the win.