During his 13-season career in Major League Baseball, he was a relief pitcher for the Cincinnati Reds (1972–73 and 1978–80), San Diego Padres (1974–77), Montreal Expos (1982 and 1986) and Pittsburgh Pirates (1983 and 1985).

[2] After appearing in 19 games for Cincinnati in 1972 and 1973, Tomlin was traded (along with Bobby Tolan) to the San Diego Padres for Clay Kirby.

[4] Tomlin was traded to the Texas Rangers after the 1978 season for Gaylord Perry, but returned to the Reds in March 1979 when they purchased his contract.

He appeared in four National League Championship series games, one in 1973 and three in 1979, and allowed eight hits and three earned runs in 42⁄3 innings pitched.

[5] Cincinnati released him on September 2, 1980, and Tomlin signed with the Toronto Blue Jays before the 1981 season, but did not appear with the major league team that year.