Rapper Danny Brown received an X-rated welcome when he performed in Minneapolis, Minnesota on Friday after a female fan offered him oral sex onstage.

The I Will star took his The Old & Reckless Tour to the city's Triple Rock venue and invited a number of ladies to join him in the spotlight, and one devotee decided to show her appreciation for the 32-year-old by getting down on her knees to pleasure the rapper - in full view of other shocked concertgoers.

An image has since hit the Internet, and reports about the sex act quickly spread across Twitter.com, prompting Brown's peer Kendrick Lamar to reach out to his pal via the micro-blogging site to find out if the rumours are true.

Lamar wrote, "u really just got the head (fellatio) on stage?", prompting a boastful Brown to reply, "...and didn't miss one bar."