Gary Martin Allenson
- Bats Right, Throws Right
- Height 5' 11", Weight 185 lb.
- School Arizona State University
- Debut April 8, 1979
- Final Game August 23, 1985
- Born February 4, 1955 in Culver City, CA USA
Catcher Gary Allenson was selected in the ninth round of the 1976 amateur draft. He had helped Team USA to the Silver Medal in the 1975 Pan American Games. He was the International League MVP in 1978, when he hit .299 with 20 home runs and 78 RBIs with the Pawtucket Red Sox. He played parts of seven seasons in the majors, primarily with the Red Sox.
In 1989, Allenson played for the Winter Haven Super Sox of the Senior Professional Baseball Association. He hit .340 in 43 games with the club. In 1990, he was with the Sun City Rays of the Senior Professional Baseball Association. He batted .313 in 10 games before the league folded.
Since his playing career ended, Allenson has been a major league coach and minor league manager. He managed the AA New Britain Red Sox in 1991 and was a Red Sox coach from 1992 to 1994 and a member of the Milwaukee Brewers staff from 2000 to 2002. More recently, he managed the Bluefield Orioles in 2006 and the Norfolk Tides in 2007.
On June 4, 2010, Allenson was brought up to Baltimore Orioles as a result of the firing of manager Dave Trembley, he took over for Juan Samuel as third base coach, while Samuel became the team's interim manager.