S.D. Codified Laws § 21-47-16
If the holder of such mortgage is not willing at such sale to bid the full amount of the judgment debt, such mortgage holder shall establish at the time of the trial by competent proof to the satisfaction of the court, the fair and reasonable value of the mortgaged premises, and the court shall determine the same in its decree. If the court shall find such fair and reasonable value, less the sum of the balances due as of the date of judgment on any prior liens or encumbrances upon the mortgaged premises, including liens or charges for real property taxes and special assessments, to be less than the sum due on said mortgage, with costs and disbursements, and costs and expenses of sale, it may by such decree authorize such mortgage holder to bid not less than the fair and reasonable value as thus determined, less the sum of the balances due, as of the date of sale, on any prior liens and encumbrances upon the mortgaged premises, including liens or charges for real property taxes and special assessments; and if a deficiency remains after the foreclosure sale, such mortgage holder shall be entitled to a general execution for such deficiency only upon application to the court in which the judgment was rendered.
SDCL 21-47-16