Anthony Smith came up short in the final fight of his career, suffering a TKO loss to Zhang Mingyang in the co-main event of UFC Kansas City on Saturday night.

The stoppage came at the 4:03 mark of the first round after Zhang brutalized Smith with elbows on the feet and then forced the finish via ground-and-pound. Zhang opened up a nasty cut on the top of Smith's head earlier in the round.

"Five years ago, that's a beatable guy," Smith said after officially retiring. "I'm aging. It is what it is."

Following the bout, Smith was visibly emotional as the UFC aired a video package featuring his career highlights.

"Lionheart" finishes his MMA career on the heels of a three-fight losing streak. Smith, a 36-year-old who fights out of Omaha, Nebraska, fell to 37-22 as a professional and 13-13 in the Octagon.

Smith, who challenged Jon Jones for the light heavyweight title in 2019, defeated the likes of Alexander Gustafsson, Rashad Evans, Mauricio "Shogun" Rua, and Volkan Oezdemir throughout his 59-fight career dating back to 2008.