The 26-year-old was unpenalized for an illegal hit to the head on Tampa Bay Lightning forward Brett Connolly near the midway point of the second period during Thursday's 3-2 overtime victory by the Caps.
"Green raises and drives his left arm into Connelly's head with significant force, making it the principal point of contact and causing it to impact the glass. This is a clear hit to the head," said NHL discipline czar Brendan Shanahan on Friday.
"When Green decides to commit to this check, Connolly already is bent over. Green sees Connolly in this position; he then slows down, waits, loads up and targets Connolly's head. We've taken into consideration that Green has been suspended once and fined once for a similar infraction during his NHL career. We have also noted that Connolly later returned to the game and played in the third period."
Green was issued a three-game ban for a hit to the head delivered to Florida Panthers forward Michael Frolik in January of 2010.
Green will forfeit $85,135.14 in salary which goes to the Players' Emergency Assistance Fund, and he will not be eligible to return until March 16 when Washington plays at Winnipeg.