In Toyotomi Chinzei Gunki (Kyushu War Chronicles by Hideyoshi TOYOTOMI), there is a description about him as, 'Shimazu Uma no kami Masahisa' (Masahisa SHIMAZU, Uma no kami), and seems that he was receiving an equivalent treatment to Taisho (general) in the Shimazu army stationed at Higonokuchi.
豊臣鎮西軍記に、島津右馬頭（うまのかみ）政久（まさひさ）とあり、肥後口の島津軍の大将格。