A method of forming a functionalized polymer, the method comprising reacting a living polymer with a compound defined by the formula ##STR00001## where R.sup.5 includes a monovalent organic group, R.sup.6 independently includes a monovalent organic group, each R.sup.7 independently includes hydrogen or a monovalent organic group, each R.sup.8 independently includes hydrogen or monovalent organic group, R.sup.9 includes a monovalent organic group, M is silicon or tin, and x includes an integer from about 2 to about 10, where R.sup.5 and R.sup.6 may optionally each independently be alkoxy groups, and where R.sup.7, R.sup.8, and R.sup.9 are non-Zerewitinoff organic groups.