In Austin Hill Country Realty, Inc., v. Palisades Plaza, 948 S.W.2d 293, 299 (Tex. 1997), the breaching tenant bore the burden of proof to demonstrate that the landlord failed to make reasonable attempts to relet the premises. In discussing this burden, the court stated that when the "tenant's contention is that the landlord failed to mitigate damages . . . it is similar to an avoidance defense; evidence of failure to mitigate is admissible only if the tenant pleads the failure to mitigate as an affirmative defense." The court did not, however, specifically discuss the burden of proof.