On Tuesday Father Paul Chavasse, the provost of Birmingham Oratory in Britain, spoke in Rome about the alleged miracle, the Times of London reports.
Chavasse is arguing Newman's case to have the 19th-century prelate proclaimed a saint.
He said an unnamed 60-year-old deacon in Boston was suffering from spinal disease and a surgery was unsuccessful.
He then prayed to Newman and now has fully recovered.
The Boston Diocese is supposed to finish their investigation by February and the results will go to the pope for review.