A method for closing an opening in tissue using a suturing device includes inserting at least a portion of a suture through a tissue tract and through a tissue wall. Following inserting at least a portion of the suture, the method includes advancing a first end of the suture through a bight of the suture, the bight pre-formed about a periphery of a knot tube of the suturing device. Once the first end is advanced, the method includes tensioning the first end of the suture and a second end of the suture adjacent the bight to form a knot affixing a loop of suture across the puncture.