Green won ten Stanley Cup titles in his time with Ottawa, four as a trainer, and six as a coach.

Peter Green began his athletic career with the Ottawa Capitals field lacrosse team as a player in 1890.

[2] He coached the Ottawa Rough Riders football team from 1900 to 1903,[1] during which they won two Canadian championships.

[1] In 1908, he was promoted to head coach to replace Alf Smith, who left to join the Kenora Thistles.

The team went 9–9 in the following 1911–12 season and lost the chance to tie for the league title with the Quebec Bulldogs after losing a replayed game to end the year.