Carleton started his National Hockey League career with the Toronto Maple Leafs. He also played with the Boston Bruins and California Golden Seals. His career would last from 1966 to 1972. He won one Stanley Cup in 1969–70 with the Bruins; Carleton was on the ice as the left wing on Derek Sanderson's line when Bobby Orr scored his famous Cup-clinching goal in Game 4 of the 1970 Cup finals. He was traded to California the 2 seasons later.
He retired in 1978.
In his NHL career, he played in 278 games and scored 55 goals and 73 assists.