The 28-year-old hip-hop star was initially thought to have chosen to remove the track because he considered his beef with Drake to have finished, but the decision was actually taken following the intervention of the WWE, according to Complex Sports.
The Philadelphia-born musician's camp was reportedly sent a letter by the WWE, insisting the controversial record be taken down because a snippet of The Undertaker's theme song was used without the permission of the organisation.
In a statement issued after the song was released, the wrestling body said: ''WWE takes its intellectual property rights very seriously and we are looking into the matter.''
Earlier this week, Mill posted a now-deleted message on Instagram saying his beef with Drake is finished.
He wrote: ''We really only focusing on making it out that's the only war we fighting .... I'm entertaining no rap/real beef over drake s/o rapper! I can't fall for the oldest trick in the book and I never shoulda entertained it bcuz it won't bring me no money or success.. (sic)''
'Smalls Change (Meditations Upon Ageing)' arrives in April.
The two awards have made for a great 72nd birthday present for the country music icon.