Listen to Jordin Sparks on iHeartRadio

Jordin Sparks and Jason Derulo are playing coy about new engagement rumors. 

The "Idol" alum sported a large diamond rock on her left ring finger at the VMAs on Sunday, but didn't have anything to say about what it could mean. 

"Billboard" says Jordin playfully stuck out her tongue and told them "I don't have anything on my hand" when they asked her about it on the red carpet. 

On Monday however, Jason released a new single from his upcoming album called "Marry Me."  It debuted on Ryan Seacrest's radio show, and Jordin later re-tweeted a message from the host saying that he thinks Jason was "talking about [her]" in the track.  

The musical couple both have projects in the works.  Jason has an EP called "Tattoos" coming out next month, while Jordin started recording her follow-up to 2009's "Battlefield" earlier this year. 

Photo Credit Getty Images & Splash News