Systems, devices and methods for fusing both sacroiliac joints of a patient using a long implant are provided. The method can include inserting a guide pin through the first ilium and across the first SI-Joint, through the sacrum and above the SI foramen, across the second SI-Joint, and through the second ilium; forming a first rectilinear cavity through the first ilium and the first SI- Joint; forming a second rectilinear cavity through the second ilium and the second SI- Joint, wherein the first rectilinear cavity and the second rectilinear cavity are aligned; and inserting an implant through the first cavity, across the first SI-Joint, through the sacrum, across the second SI-Joint, and through the second cavity.