Tenn. Code Ann. § 20-2-217: Extraterritorial personal service - Proof

(a) In addition to service of process on the secretary of state as set forth in this part, personal service of process may be made upon any party outside the state by any person over eighteen (18) years of age and not a party to the action. No order of court shall be required to constitute such person a proper officer to receive and execute the process.

(b) An affidavit of the person serving the process shall be filed with the clerk of the court in which the action is pending, stating the time, manner and place of service.