Any party in whose favor a judgment has been rendered may remit any part thereof in open court, or by executing and filing with the clerk a written remittitur signed by the party or the party's attorney of record, and duly acknowledged by the party or the party's attorney. Such remittitur shall be a part of the record of the cause. Execution shall issue for the balance only of such judgment.
Tex. R. Civ. P. 315