The Maple Leafs and Orr agreed to terms on a four-year deal Wednesday shortly after the NHL's free-agent shopping season began at noon. Toronto general manager Brian Burke has repeatedly said since he took over last season that it was his intent to make the Maple Leafs tougher.
Orr has piled up more than 100 penalty minutes each of the past three seasons. He had 52 fighting majors during that time with the Rangers.
The 27-year-old forward is joining his third Original Six team after stops in Boston and New York.