It meant four days of strikes coming immediately after a four-day bank holiday weekend.
New figures obtained by the Chronicle from NHS England show that almost half of all doctors at the Gawber site are junior.
Figures from NHS England show there were the equivalent of 192 full-time junior doctors working at Barnsley Hospital NHS Foundation Trust as of December - 47.1 per cent of the 408 doctors working at the trust.
Across England there were 66,000 junior doctors working for hospital and community health services as of December 2022, making up 49.9 per cent of all clinicians.
Any doctor below consultant level is referred to as ‘junior’, meaning junior doctors encompass doctors just starting in the NHS and those who have been training for many years for specialist positions.
They receive a wide range of salaries, with ‘Foundation Year One doctors’ - the most junior category - starting on £14.09 an hour, or around £29,000 a year.
Barnsley Hospital has 25 such doctors working at the trust at this point, alongside a further 26 second year foundation doctors.
The number of junior doctors has been increasing across England over the past decade as part of a wider uptick in clinicians working for the NHS.
In December 2019, prior to the coronavirus pandemic, there were the equivalent of 57,000 full-time junior doctors, representing 48.7 per cent of the workforce.
Barnsley Hospital had 157 junior doctors at this point, or 43.9 per cent of all doctors working at the organisation.
A Barnsley Hospital spokesperson said delays are expected to carry on past tomorrow.
They added: “It’s very likely disruption to services will continue into the weekend following the strike action, so please bear with us if this is the case.
“We thank you for your patience and understanding, and would like to reassure you that, as always, patient safety remains our absolute priority throughout the Trust.
“We expect the will be significant delays in the Emergency Department as patients will be seen according to their immediate needs.”
George Arthur, the secretary of Barnsley Trades Union Council, told the Chronicle that the striking doctors are ‘very pleased’ at the support they are receiving.
He added: “It’s important that the junior doctors win this dispute.
“Without decent pay we won’t have the staffing to keep the NHS going.
“This year marks the 75th anniversary of the NHS.
“We have to force the government to provide the funds that will ensure it goes on to celebrate it’s centenary.”