Britney Spears Slams Justin Timberlake Over Apology, Cry to Mommy

Britney Spears is coming after Justin Timberlake for taking back his apology to her from a few years ago -- and she's going even further back to slam him ... and his skills on the court.

The pop star just posted a photo of a basketball hoop with the moon in the background that looks like a ball going through. It's a cool shot, but her caption is even more telling -- 'cause she kinda goes scorched earth on her ex after his little stunt last night.

She writes, "Someone told me someone was talking s*** about me on the streets !!! Do you want to bring it to the court or will you go home crying to your mom like you did last time???"

Britney emphatically adds one last dig that's pretty good, TBH ... writing, "I’m not sorry!!!"

Of course, she's referring to JT issuing his non-apology in front of a NYC crowd Wednesday -- when he performed for a one-night show. You'll recall, right before he launched into 'Cry Me a River' -- which is famously known to be about Brit -- he said ... he'd like to take the opportunity to apologize to "absolutely f***ing nobody."

A lot of Britney fans were upset with the fact that he flip-flopped ... especially, seemingly, out of nowhere. Mind you, Britney herself had just recently apologized to Justin about stuff in her memoir.

It's also interesting that Britney is bringing up this basketball stuff again. Remember, she actually crapped on his b-ball ability (or lack thereof) late last year out of the clear blue.

Basically, she says she beat him a ton when they were dating ... and that he sucks. Now, she seems to be implying that he was bent out of shape over it, and maybe even cried.

Weird flex, but okay ... Britney's out here flaunting her stuff. Love to see it!