Haynes started his National Hockey League career with the Montreal Maroons. He would also play with the Boston Bruins and Montreal Canadiens. His career lasted from 1931 to 1941. Haynes played in 390 NHL games, scoring 61 goals and 134 assists.
He played for the Montreal AAA team that won the Allan Cup in 1930. The next year he turned pro, playing for the Montreal Maroons of the NHL and their farm team the Windsor Bulldogs. Haynes continued to play for the Maroons until he was traded to the Boston Bruins in December, 1934. He finished off the season with the Bruins and then was traded back to Montreal - this time to the Canadiens.
Haynes played for the Canadiens for five more seasons and retired in 1941.