John Mayer denies throwing shade at Taylor Swift on her birthday

While Taylor Swift's pals were celebrating her 27th birthday on social media on Tuesday, the "Shake It Off" singer's ex-boyfriend, John Mayer, was throwing shade at the day.

"Tuesday, December 13 may be the lamest day of the year, conceptually," the 39-year-old singer tweeted.

Mayer promptly deleted the tweet but not before screenshots were taken and reshared. After being accused by some of dissing Swift, he clarified his message, writing: "NOPE. No. Nuh-uh. People I am 39. I am deleting those tweets. Come right at me for doing so. Absolutely no shade."

WATCH: John Mayer's Exes Katy Perry and Jennifer Aniston Happily Pose Together on Red Carpet

Mayer also deleted that tweet, only to repost it on Wednesday morning with another note. "Looks like I shouldn’t have deleted this tweet…" he wrote.

Swift dated Mayor briefly from November 2009 to February 2010. After the two split, Swift penned "Dear John" that included some pretty telling lyrics. "Dear John, I see it all now that you're gone. Don't you think I was too young to be messed with?" she sings in the chorus.

EXCLUSIVE: John Mayer Talks New Music, Accidentally Reveals Upcoming Album Title

When speaking to Rolling Stone in 2012, Mayer admitted that he wasn't too pleased with the song. "I never got an email. I never got a phone call," he said of Swift releasing the track. "I was really caught off-guard, and it really humiliated me at a time when I'd already been dressed down. I mean, how would you feel if, at the lowest you've ever been, someone kicked you even lower?"

Despite their differences, Swift and Mayer still run in the same circles. The two were both at Drake's 30th birthday party in October, along with Mayer's other ex, Katy Perry.