Clark v. Trailways, Inc
In Clark v. Trailways, Inc., 774 S.W.2d 644 (Tex. 1989), the Supreme Court held that even though Trailways had filed a pretrial motion for sanctions that included an objection to an undisclosed witness testifying, the objection was waived be cause there was not a timely objection when the witness actually testified.
The Supreme Court explained that requiring another objection at the time of the trial gave the trial court an opportunity to review any previous finding of good cause, while providing litigants and the courts alike with the uniform and consistent rule regarding the preservation of error under Rule 215(5). TEX. R. CIV. P. 215(5). Rule 215(5) dealt with discovery abuse.