1966 Washington Senators season

The 1966 Washington Senators season involved the Senators finishing eighth in the American League with a record of 71 wins and 88 losses.

Offseason

 * October 12, 1965: Woodie Held was traded by the Senators to the Baltimore Orioles for John Orsino.
 * November 19, 1965: Don Zimmer was released by the Senators.
 * November 29, 1965: Bob Saverine was drafted by the Senators from the Houston Astros in the 1965 rule 5 draft.

Regular season

 * Emmett Ashford, the first black umpire in Major League Baseball history made his debut at D.C. Stadium on April 9, 1966.

Opening Day starters

 * Ed Brinkman
 * Doug Camilli
 * Joe Cunningham
 * Ken Hamlin
 * Frank Howard
 * Don Lock
 * Ken McMullen
 * Pete Richert
 * Fred Valentine

Notable transactions

 * April 5, 1966: Al Closter was purchased by the Senators from the Cleveland Indians.
 * April 13, 1966: Diego Seguí was purchased by the Senators from the Kansas City Athletics.
 * July 30, 1966: Diego Seguí was traded by the Senators to the Kansas City Athletics for Jim Duckworth.

Draft picks

 * June 7, 1966: Del Unser was drafted by the Senators in the 1st round (18th pick) of the secondary phase of the 1966 Major League Baseball Draft. Player signed June 28, 1966.

Starters by position
''Note: Pos = Position; G = Games played; AB = At bats; H = Hits; Avg. = Batting average; HR = Home runs; RBI = Runs batted in''

Other batters
''Note: G = Games played; AB = At bats; H = Hits; Avg. = Batting average; HR = Home runs; RBI = Runs batted in''

Starting pitchers
Note: G = Games pitched; IP = Innings pitched; W = Wins; L = Losses; ERA = Earned run average; SO = Strikeouts

Other pitchers
Note: G = Games pitched; IP = Innings pitched; W = Wins; L = Losses; ERA = Earned run average; SO = Strikeouts

Relief pitchers
Note: G = Games pitched; W = Wins; L = Losses; SV = Saves; ERA = Earned run average; SO = Strikeouts