(1) When in the discretion of the court it shall be deemed advisable in the interests of the furtherance of justice, the court may direct that not more than three (3) jurors in addition to the regular jury be called and impaneled to sit as alternate jurors. Alternate jurors, in the order in which they are called, shall replace jurors who, prior to the time the jury retires to consider its verdict, become unable or disqualified to perform their duties.
(2) Alternate jurors shall be drawn in the same manner, shall have the same qualifications, shall be subject to the same examinations and challenges, shall take the same oath, and shall have the same functions, powers, facilities, and privileges as the regular jurors. An alternate juror who does not replace a regular juror shall be discharged after the jury retires to consider its verdict.
(3) Each opposing side shall be entitled to one (1) peremptory challenge in addition to those otherwise allowed by law. The additional peremptory challenges may be used against an alternate juror only, and the other peremptory challenges allowed by these rules by this section may not be used against an alternate juror.