Patrick Mathis is in his first year with the ThunderBolts and third as a professional in 2019. He signed as a free agent on November 14, 2018. His career began in 2017, when he was selected in the 22nd round of the Amateur Entry Draft by the Houston Astros out of the University of Texas. He played in 58 games over two years in the Astros' system, reaching as far as high-A and batting .221 overall. In three years at Texas, Patrick hit .263 over 108 games, including .297 as a sophomore in 2016. He hit 13 collegiate home runs and drove in 55 runs. He attended Venus High School in Venus, Texas.