Fleming played four full seasons on a talented Chicago club alongside stars like Bobby Hull, Stan Mikita, Glenn Hall and Pierre Pilote.

Left unprotected in the 1970 expansion draft, Fleming joined the Buffalo Sabres, where he recorded his career high in penalty minutes in 1970–71, his last NHL season.

Subsequently he was dropped and reclaimed five separate times by the Sabres in the 1971 NHL intra-league draft due to a loophole the team thus exploited.

After minor league stints with the Cincinnati Swords (AHL) and the Salt Lake Golden Eagles (WHL) in 1971–72, Fleming returned to Chicago, joining the Cougars of the newly formed WHA.

While recovering from a stroke and heart attack Fleming resided at the Claremont Rehab and Living Center for 5 years where he died.

During this time his son, Chris Fleming, filmed his situation and conversations in the hope of reaching his father's fans through YouTube and the internet.