LOL! KIM KARDASHIAN GETS KNOCKED THE F**K OUT! STAY IN YA LANE KIM!

Kim Kardashian's a knockout. Literally.
The reality TV star put her good looks on the line on Tuesday in a charity boxing match – and one female fan laid a blow right on Kim Kardashian's kisser, according to the U.K.'s Daily Mail.

The buxom beauty stepped into the ring dressed in head-to-toe pink Everlast gear, but she was soon bested by her opponent, who was the highest bidder in an auction benefiting The Dream Foundation at the Commerce Casino in Commerce, California.

"About to start boxing! In my physical! I'm sooo scared!!!!" Kardashian tweeted earlier in the day, also posting pix of herself getting her blood pressure checked before the bout.

But despite gamely facing her fears in the end, the 29-year-old socialite almost canceled her match after her younger brother, Rob, was KO'ed in an earlier fight.

When her 22-year-old bro was floored in a barrage of jabs in the first round, Kim reportedly jumped into his corner and demanded the bout be stopped, claiming the larger opponent was going too hard on him.

That left Kim as the only "Keeping Up With the Kardashians" member to rumble in the ring, although family members including stepfather Bruce Jenner, mother Kris, sisters Khloe and Kourtney, and Kourtney's boyfriend Scott Disick, cheered her on in the audience.