A suture anchor assembly and a method of tissue repair using the assembly. The assembly includes a soft suture anchor formed of a flexible tubular sheath with opposing open ends which receives a suture strand from a suture construct. The suture strand has a tensioning free end and an opposite tissue-fixation end. A tissue-fixation device, such as a disk, is coupled to the tissue-fixation end of the suture strand. The suture strand has uni-directional barbs which allow one-way tensioning, to provide secure fixation of soft tissue to bone as the strand is pulled through the sheath of the soft anchor.