Unsurprisingly, it sent the football world into a meltdown as fans tried to decipher if Musk really intends to buy Manchester United.
The iconic football club is in tatters after finishing sixth in the English Premier League last season.
United hired respected Dutch coach Erik ten Hag but has lost their first two games of the season against middling opposition and are on the bottom of the EPL ladder for the first time in 30 years.
The Red Devils are currently owned by the American Glazer family, who also own the Tampa Bay Buccaneers in the NFL.
The Glazers are widely disliked by United supporters for their mismanagement of the team since taking it over in 2005, but have refused to sell the club on multiple occasions.
This week, Musk sold $US6.9 billion (about $A10 billion) of Tesla stock, which would give him more than enough funds to meet the Glazers' valuation last year of $US4 billion for the club.
But Musk has a long history of trolling his followers on Twitter, and bemused commenters were unsure what to make of his post.
Journalist Kanishka Raj Singh joked: "When Elon Musk finds a way to send normal people on this planet to Mars, he should send Manchester United there first because they are surely not capable of winning any trophies in this world."
The AFR's Mark Di Stefano said: "Thoughts are with the tech and football writers who just had to down tools and chase comment and reaction to a trolling tweet."
Musk famously bought Twitter for $44 billion ($A60.9 billion) earlier this year but terminated his deal to buy the social media giant last month.
He previously accused Twitter of "resisting and thwarting" his attempts to access information about fake accounts, saying the deal could not progress until the issue was settled.
Time will tell if the 51-year-old, who has a net worth of $US265 billion, follows through on his latest tweet.
