Gregory Scott Booker (born June 26, 1960)is a former professional baseball pitcher. He pitched in all or part of eight seasons in Major League Baseball, from 1983 until 1990. He also served as a coach for the San Diego Padres from 1997 until 2003, the first four years as bullpen coach, then a season-plus as pitching coach. He is currently a scout for the Los Angeles Dodgers.
Booker's wife, Kristi, is the daughter of long-time major league manager Jack McKeon and his son Zach is a catcher in the minor leagues.
On June 29, 1989, McKeon, often called "Trader Jack", traded his own son-in-law to the Minnesota Twins for pitcher Freddie Toliver.