Tanner Rainey joined the Nationals in 2019 after debuting with the Reds and earned a World Series ring despite a 6.75 ERA during the postseason. He had a promising start with a 3.54 ERA from 2019 to 2020, but his performance declined significantly in 2021 with a 7.39 ERA. After undergoing Tommy John surgery, he returned in 2024 but posted a 4.76 ERA across 50 appearances. For his career, Rainey holds a 5-10 record with a 5.23 ERA and a -0.1 WAR.