A medical tool may comprise a sheath and an elongate instrument. The sheath may comprise a tubular shaft member including a sheath channel and a guard member coupled to a distal portion of the tubular shaft member. The guard member may comprise a rigid distal section and a flexible proximal section that is more flexible than the rigid distal section. The elongate instrument may be sized for passage within the sheath channel. The elongate instrument may comprise a flexible tubular section and a rigid tip extending from a distal portion of the flexible tubular section.