A 34-year-old Rotherham man has been arrested on suspicion of causing death by dangerous driving.
He has been released on bail pending further enquiries.
A 37-year-old woman arrested yesterday in connection with the collision has also been released on bail.
She was initially arrested on suspicion of causing death by dangerous driving but has now been arrested on suspicion of assisting an offender.
Two other people are assisting police with their enquiries.
Police were called to the incident near to the M1 junction 31 roundabout, at around 1am yesterday (Sunday, 6th July).
A man died as a result of the collision and a 29-year-old woman remains in a critical condition in hospital.
The man has not yet been formally identified.
It is believed they were riding a moped and were in collision with a BMW car.
The A57 was closed for more than 12 hours on Sunday between the B6067 Worksop Road and A618 Mansfield Road as a result.
Witnesses, or anyone with information, should contact the police on 101.
Alternatively call Crimestoppers anonymously on 0800 555111.