Smithson pitched for eight years in the big leagues, going 76-86 with a 4.58 ERA. After spending seven seasons in the minors he finally reached the majors in 1982 with the Texas Rangers. He won 10 games for the Rangers in 1983 but was traded to the Minnesota Twins at the end of the season. Smithson strung together three solid years for Minnesota. He won 15 games in 1984 and again in 1985, then 13 more in 1986. However, his ERA ballooned to 5.94 in 1987 and the Twins released him after the season. Smithson caught on with the Boston Red Sox and pitched in 71 games over the next two years, which would conclude his career.
Smithson was a member of the 1987 Twins’ team that won the World Series. However, he did not participate in the postseason.
When he was in the minors, Smithson pitched for the Pawtucket Red Sox in a 33-inning game against the Rochester Red Wings on April 18, 1981. He threw 3 and 2/3 scoreless innings in the contest, which lasted so long it was eventually suspended and restarted the following day. Pawtucket won the game 3-2.
Mike Smithson – career stats