(a) The jurors drawn for jury service shall be assigned at random by the clerk to each jury panel in a manner prescribed by the court.
(b) If there is an unanticipated shortage of available petit jurors drawn from the jury wheel the court may require the sheriff to summon a sufficient number of petit jurors selected at random by the clerk from the jury wheel in a manner prescribed by the circuit court.
(c) If there is an unanticipated shortage of available grand or petit jurors, qualified jurors that have not yet served on a jury in the current term may be used to replace needed jurors.