The former couple, who split in 2009 after Brown assaulted his then-girlfriend, sat at different tables at a club here but onlookers say they were very aware of one another inside the club, reported New York Post online.
"After Chris made his way into SL with a group of friends, Rihanna pulled up with her own group of friends. The infamous exes sat far enough from each other to not be able to talk, but close enough to keep an eye on one another. Chris sent Rihanna two bottles of Ace of Spades Champagne. DJ Sinatra had both Rihanna and Chris dancing at their tables," an onlooker said.
The meeting comes a few weeks after Rihanna came face-to-face with Brown and his current girlfriend Karreueche Tran at a Los Angeles club but things were not so friendly.
Rihanna and Brown recently worked together on two tracks, 'Turn Up the Music' and 'Birthday Cake'.