The 'We Found Love' hitmaker was spotting canoodling with the basketball star at Veranda nightclub in New York earlier this month and eyewitnesses say Rihanna appeared "really into him".
19 May 2012 A source told In Touch Weekly magazine: "They were very flirty in the club all night and holding hands. She was sitting on his lap and was really into him."
The sportsman is a controversial figure, in March he was fined $25,000 by the National Basketball Association (NBA) after tweeting a photo of a woman's ass in a thong from his bed.
A source said: "He is the team's most controversial player, so it's no wonder that Rihanna likes him."
Rihanna recently unfollowed former boyfriend Chris Brown on twitter after speculation emerged that an offensive song he released is aimed at the Bajan beauty and infers that she is promiscuous.
Chris - who also "unfollowed" Rihanna on twitter following her actions - posted a link on the social networking site to his freestyle version of Kanye West's 'Way to Cold'.
In the song, he raps: "Don't f**k with my old b*****s ... like a bad fur ... every industry n***** done had her."
The rap continues: "Trick or treat like a pumpkin ... just to smash her."
Katy Perry has reportedly spent $1 million on refurbishing the home she shared with estranged husband Russell Brand.
The 'Part Of Me' singer wants to drastically alter the Los Angeles mansion - which she bought with 'Forgetting Sarah Marshall' funnyman Russell - in order to move on from her soon-to-be ex-spouse.
A member of Katy's entourage told The Daily Star newspaper: "Katy's fed up of having memories of Russell everywhere. They bought the house together last year after getting married but she's decided to completely refurbish it.
"It's under construction and has been for a few months since their divorce. It's not easy for Katy to move on with her life following their split, as her home is full of wedding memories."
Russell, 36, has paid 27-year-old Katy his share of the $7 million mansion and the 'Firework' hitmaker is keen to make it her own.
The source added: "It's now her house and she wants to completely change the colour inside and add some crazy decor and furnishings.
"Katy can't bear to sell it, she loves it. But she's there all alone with her two cats and her brother so needs it to feel like home."
The couple - who were married for 14 months - signed divorce papers in February although their split will not be finalised until June 30.