Sagatsukasa Hiroyuki (Japanese: 磋牙司 洋之, born 21 December 1981 as Hiroyuki Isobe (磯部 洋之)) is a retired Japanese professional sumo wrestler from Mishima, Shizuoka. A former amateur competitor at Toyo University, he made his professional debut in March 2004, reaching the top makuuchi division for the first time in March 2010. He won a makushita and a jūryō division championship. His highest rank was maegashira 9. He was one of the shortest wrestlers in professional sumo at 1.66 m (5 ft 5+1⁄2 in).