It is a rare three-quarter portrait by the artist, in the so-called “emperor format” compared to the more common “head format” of his vast range of portraits. This portrait is to be added to the small group of only three cardinals known to date with the subject standing (while few other cardinals are known), always in “emperor format”, but with the prelate sitting on a ceremonial chair like the ones of Flavio Chigi (Ariccia, Palazzo Chigi), Carlo Cerri (London, National Gallery). The Cardinal is to be identified in Bonaccorso Bonaccorsi (Monte Santo, 1620 – Bologna, 1678), as demonstrated in comparing an engraving by Albert Clouwet derived from a painting by Jacob Ferdinand Voet, present in the collection Effigies nominates and cognomine cardinalium nunc viventium, printed by Giacomo De Rossi alla Pace in several editions (Ariccia, Palazzo Chigi; Vatican Apostolic Library, etc.). This engraving was probably taken from a previous pose, dating back to the time of the nomination of Bonaccorso to the role of Cardinal in 1669, while portrait under discussion would be from no more than a few years later, showing the prelate looking more mature. Presumably, it was painted in 1673, on the occasion of the appointment of Bonaccorsi as Papal Legate in Bologna by Clement X, given the official clothing he is wearing.