NHS supremo Amanda Pritchard confirmed the plan at a meeting of NHS England's board, as the ongoing concerns over Shrewsbury & Telford Hospital NHS Trust (SaTH) were discussed at the highest level of the health service.
The trust, which manages both Royal Shrewsbury Hospital and Princess Royal Hospital Telford, has been in special measures since 2018.
It is also the subject of a review into its maternity services that has seen more than 1,800 patients come forward with complaints, with the police also launching an investigation into whether there should be criminal action over the care.
Now Mrs Pritchard, chief operating officer of NHS England and NHS Improvement and chief executive of NHS Improvement, has said that an "improvement team of unprecedented scale" has gone into the trust tasked with turning it around.
A paper presented to the NHS England board by Mrs Pritchard and Stephen Powis, the NHS national medical director, explained that some of the team had already begun, but a formal start will take place tomorrow.
The report said: "This team have been rapidly brought together and some are already working in the trust, but a formal commencement event is planned for 31 of July."
Louise Barnett, chief executive of The Shrewsbury and Telford Hospital NHS Trust (SaTH), said: “We know that further improvements are needed at pace and we welcome the strengthened package of support announced by NHS Improvement.
“The range of measures include senior on-site support to help drive improvements in both quality and safety. This means bringing in more health professionals with senior experience to join teams and share best practice and learning across our hospitals.
“As a trust, we are determined to deliver the improvements that our patients, staff and communities want to see and rightly deserve.”
Mr Baker's letter, which came after an inspection last month, sparked serious concerns over the situation at the trust and led to top-level NHS meetings which have seen the specialist improvement team set up.
He had said: "Our most recent inspection on June 9 and 10, 2020, has resulted in further enforcement action being issued despite us having very limited confidence that this will drive any meaningful improvement.
"This failure to improve demands further action and, as the independent regulator, our only remaining option is to consider recommending Trust Special Administration."
Mr Baker said CQC teams had carried out five inspections at the hospitals since 2018 and had used new inspectors, alongside those who had previously carried out the checks, on each occasion so as to ensure 'fresh eyes' on the issues.
However, he said that the 'fresh eyes' had "consistently identified institutional failings, supported by examples of poor care, consistently articulating SaTH as a significant outlier."
He added: "Equally, specialist advisors who have supported previous inspections of SaTH have expressed concerns of an overall worsening picture when compared to their previous findings."
Mr Baker also suggested that the issues at the hospital were not related to a lack of staff or too many patients.
He said: "Our most recent inspection found significant safety concerns; this was despite staffing levels being such that there was no reason to attribute poor practice to high demand or poor staffing levels."