The isolation and structural characterization of alkynyl Ru-alkylidene species has been elusive owing to their rapid metallotropic shift and fast turnover. The enyne ring-closing metathesis and relay metathesis provides the platform to form a variety of alkynyl Ru-alkylidene species possessing a sterically and electronically different substituent on the carbenic carbon, which allowed their regio-controlled trapping and structural characterization.