But the pair of Sprint Cup Series champions have since appeared to bury the proverbial hatchet, even though their 2011 "disagreements" and Busch's supposed head games may have contributed to Johnson's worst finish in a season (6th) since 2005, the year before his first championship.
So it isn't totally out of the blue that Busch would come to Johnson's defense in the reigning Cup champion's feud with former NFL quarterback Donovan McNabb, but it sure is interesting.
In case you forgot to use the internet at any point in the past week, McNabb, an analyst on FOX Sports Live, made the claim that Johnson and other NASCAR drivers are "absolutely not" athletes.
Johnson, ever the classy gentleman, brushed off McNabb's comments by suggesting during his champion's media tour on Monday that his opinion is actually good for NASCAR because it brings more attention to the sport.
Chatter has since died down, but then Busch decided to stir the pot once again on Thursday.
Busch Whacked, of course, is Busch's military inspired mud-run at Texas Motor Speedway, held the last two years.
Both Johnson and McNabb have yet to respond (it's unlikely that either will) but while Johnson chose the diplomatic route, it's possible that drivers will continue to drum up the conversation until McNabb changes his mind.
Even Kevin Harvick, Busch's new teammate at Stewart-Haas Racing in 2014, got in on the conversation.
Really funny @KevinHarvick— Donovan McNabb (@donovanjmcnabb) November 20, 2013