Former Chesterfield boss John Sheridan endured a miserable return to his old side as Plymouth lost 2-0 in an eventful clash.
Matty Brown put Chesterfield ahead on his league debut before Marc Richards converted a penalty but Brown was sent off in the second half as Plymouth's Reuben Reid had a penalty saved.
Chesterfield struck first when a corner to the back post found Brown who scored with a downward header from eight yards but Plymouth should have levelled in the 25th minute but Romuald Boco blazed over from 10 yards.
There was a lengthy stoppage after Chesterfield striker Armand Gnanduillet injured a shoulder and was replaced in the 34th minute but the home side increased their lead in the 42nd minute through a Richards spot-kick after a linesman spotted a foul on the striker.
Lewis Alessandra was denied by Tommy Lee in injury time and Plymouth had another chance to get back in the game when Brown was sent off for a foul on Caolan Lavery but Lee saved Reid's 64th- minute penalty.