David Ritchie Machemer (/ˈmɑːkɛmər/ MAHK-eh-mer;[1] born May 24, 1951) is an American former professional baseball player, scout, and minor league manager.

[2] Machemer threw and batted right-handed, stood 5 feet 11 inches (1.80 m) tall and weighed 180 pounds (82 kg).

He made his major-league debut at the age of 27 for the California Angels on June 21, 1978, playing second base and leading off against the Minnesota Twins.

Machemer also spent time as a minor league manager or coordinator with the Milwaukee Brewers (1985–91), Montreal Expos (1992–95) and the Orioles (1996–2002).

Machemer came to the San Francisco Giants' system in 2005 after working the previous three years with the Montreal Expos organization (2002–04).