Mass. Gen. Laws ch. 244, § 29: Execution for possession

Section 29. The court may at the same time order that, if the defendant neglects or refuses to accept the money or other act required by the judgment to be paid or performed, the money shall be left for his use with the clerk of the court, or such other act done as the case requires; and the plaintiff, having performed all acts required by the judgment, may have execution for possession of the land.