The Boston Celtics signed 6-8 high school rookie Gerald Green to a contract, ESPN.com is reporting.  

Green, thought by most to be a high lottery pick, slipped all the way down to number 18 where the suprised Celtics quickly pounced, making it three years in a row the team had selected a player directly out of high school.

All first-round rookie contracts are two years with separate club options for the third and fourth years.