Mo. Rev. Stat. § 429.340
Upon sale and execution of deed for the property sold in such equitable action, either by special commissioner appointed to make said sale or by the sheriff or successor of such commissioner or sheriff, the court may order delivery of possession of the premises sold to the purchaser at such sale and enforce such order by writ of assistance or other proper process against all persons to said action and all persons bound thereby, including those whose interests did not appear of record at the commencement of said action and all persons becoming interested in said property or obtaining possession thereof after the commencement of said action, which shall be the filing of the petition therein. And the court shall have full power and jurisdiction to speed said action and require service of process to be obtained speedily upon all parties therein at the instance of any party either plaintiff or defendant in said action or of its own motion.
§ 429.340, RSMo