The 54-year old Rafael produced an impressive .301/.424/.495 slash line for the Railroaders in 2018, though injuries limited him to 31 games. Among Railroaders with at least 100 at-bats, Palmeiro led the team in on-base percentage and slugging percentage, while finishing second in batting average. On May 21 against the Fargo-Moorhead RedHawks, he became the oldest player in professional baseball history to homer in a game, connecting in the bottom of the fifth inning against RedHawks starter Trey McNutt.

Over the course of his 20-year Major League career that spanned from 1986 to 2005, Palmeiro piled up 569 home runs and 1,835 RBI, earning four All-Star selections. The Colleyville, Texas, native played in 2,831 games for the Chicago Cubs, Texas Rangers and Baltimore Orioles, a total that ranks 19th in MLB history heading into the 2019 season. Palmeiro produced at least 38 home runs and 100 RBI in nine consecutive seasons from 1995 to 2003, securing his place as one of just 27 players in MLB history with at least 500 home runs.