Rihanna and Chris Brown shocked viewers when they sat together front row and cuddled at the 55th annual Grammy Awards on Feb. 10, and the Bajan beauty later sparked a rumor when she performed her single Stay - she wore a simple diamond ring on her wedding finger.

View photos of Rihanna's simple diamond ring on her wedding finger here

Dressed in a black gown and a diamond necklace with flowing two-toned blonde tresses, the Diamonds singer's performance went viral on Twitter when fans tweeted asking if it was an engagement ring or a promise ring on her wedding finger.

"Rihanna engaged?!?! Or that's some type of promise ring?" tweeted one curious fan.

"Is that a wedding ring on Rihanna?" another person asked.

The couple walked the red carpet separately when they arrived at the Staples Center in Los Angeles but sat front row together. As Brown kept his arm wrapped around her shoulder, Rihanna wore three diamond rings on her left hand to accent her custom red Azzedine Alaia gown. Later, when she performed solo, she wore the single band.

When the couple was seen after the awards ceremony, Rihanna wore the simple diamond ring again.

Rihanna performed Stay at the Grammy Awards. Wearing a black outfit, she wowed the audience with her rendition of the song with Mikky Ekko. Although rumors suggested that the pair would perform a song together, Brown did not join RiRi on stage. The Barbados beauty also took home a Grammy award herself for the Best Short Form Music Video for We Found Love. 

Rihanna went with Brown for a court appearance last week to address issues surrounding his completion of community service. Rihanna's show of support by attending the hearing was unexpected because Brown was sentenced with 200 hours of community service as part of his probation after he was convicted for assaulting her on the eve of the Grammys in 2009.