Paul Edward Siebert (born June 5, 1953) is a former Major League Baseball pitcher. He pitched parts of five seasons in the majors, from 1974 until 1978. Paul's father was former major league first baseman Dick Siebert.
Siebert was selected in the 3rd round (58th overall) of the 1971 amateur entry draft by the Houston Astros. He made his major league baseball debut with the Astros in 1974, and was traded to the San Diego Padres before the 1977 season.
Siebert was part of the infamous "Saturday Night Massacre" in New York. On June 15, 1977, the Mets traded Dave Kingman to the San Diego Padres for Siebert and Bobby Valentine, sent Tom Seaver to the Cincinnati Reds for Pat Zachry, Doug Flynn, Steve Henderson and Dan Norman, and Mike Phillips to the St. Louis Cardinals for Joel Youngblood. Siebert split the rest of that year as well as 1978 between the Mets and the minor league Tidewater Tides.
Siebert was traded to the Cardinals after the 1978 season, but was released at the end of spring training in 1979. He signed with the Montreal Expos, playing for the Denver Bears in 1979 before retiring.