Cardi B Defends Stefon Diggs Amid Allegations, Confident Chef's Lying

9:39 AM PT -- Cardi B has deleted her post ... although it's unclear why she decided to scrub it from her account.

Cardi B's proving she's a ride or die for her man -- vehemently defending Stefon Diggs as he faces serious charges ... saying his former personal chef never previously accused the star WR of getting physical.

The support came amid a tense social media exchange on Monday ... when one user pointed out Diggs' charges stemming from allegations made by his ex-employee, who claimed he choked and slapped her over a salary dispute in early December.

Cardi was having none of it ... clapping back and making it clear she won't tolerate any negative talk directed at Diggs -- 'cause she claims she has all the proof she needs to believe the chef is lying through her teeth.

"Not once has that woman said anything to me about being touched.. NOT ONCE!!," Cardi said on X ... while also posting a screenshot of a text she claims is from the chef, but the full context of the exchange is unclear.

"Mind you, we was talking every single day until she left that house and she JUST wrote me this.. but I’m gonna let the courts handle s*** and when it gets handled I want all yall talkin s*** on your f***in knees with apologies just as loud the way yall been harassing over a lie… and I put that on my two month old son in the name of the lord!! That’s how confident I am."

Cardi's stance echoes what Diggs' attorneys also said last week -- claiming the allegations are simply untrue. The Patriots are siding with Diggs as well ... and he went on to have three catches for 43 yards on Sunday against the Miami Dolphins.