A 92-year-old man died after a health board failed to give appropriate wound treatment in a "heartbreaking injustice", a watchdog has said.
Evan Jones was recovering from a hip operation at County Hospital, near Pontypool, Torfaen, in October last year, but died of pneumonia.
The Public Services Ombudsman said staff "failed to identify, manage and treat" his post-operative infection.
Aneurin Bevan University Health Board accepted the findings and apologised.
Mr Jones's son, Brian, said it was clear his father's surgery wound was "severely infected".
"The surgeon came to see us and he said the hip joint was that badly infected they had to take the hip joint out altogether... but he wasn't well enough and he ended up getting pneumonia and dying," he said.
Ombudsman Nick Bennett said: "There was a failure in terms of using the right sort of dressings, of making sure the patient and the wound were reviewed properly, that the right advice was available and the right action was taken at the right time.
"Unfortunately, the patient died of hospital-acquired pneumonia.
"Clearly, if this infection had have been dealt with properly, they would have been in a much stronger position and may not have developed the pneumonia, so this is a real injustice."
He also said the case was reflective of "cultural issues" in how health boards dealt with feedback from patients and their families.
Mr Bennett recommended the family be offered £2,000 in recognition of the failures and the health board share the outcome of the complaint with staff.
A health board spokeswoman said it "unreservedly apologised", adding that its thoughts remained with the family.
"We have made the necessary improvements to ensure that this does not happen again and are finalising a detailed action plan which sets out the further actions we will take to meet the recommendations outlined in the ombudsman's report," she said.