Rumor has it -- or should we say "Rumer" has it? -- there was a very special guest in the audience during the Season 21 premiere of ABC's “Dancing With the Stars.” Rumer Willis, who won Season 20 of “DWTS” -- along with her partner Val Chmerkovskiy -- attended the opening night of the hit series' new season.

The previous Mirror Ball champion -- a daughter of Bruce Willis and Demi Moore -- teased her attendance on Twitter when she revealed to thousands of followers that she wouldn’t be spending her Monday night on Broadway.

“Just to clarify my Broadway debut in @ChicagoMusical is not tonight. It’s next week,” she tweeted. “Tonight I have another important place to be…”

Little did fans know that place happened to be on the ballroom floor!

Willis sat on the sideline during the lively premiere, cheering on her former partner, who was teamed up with Tamar Braxton during the new installment. (Chmerkovskiy and Braxton earned a 23 out of 30 for their feisty Quickstep during episode 1.) But that wasn’t the only blast from “DWTS” past that Chmerkovskiy received. The Cha-chaing hunk’s Season 18 sidekick Danica McKeller, who finished sixth during the competition, also joined in on the foot-tapping fun as she supported her former partner with Willis from the crowd.

This isn’t the first time Willis has shown her support for Chmerkovskiy and Braxton. During the reveal of Season 21’s official celebrity roster, Willis unveiled that she would be cheering on Team ValenTay when “DWTS” returned to the small screen.

“You guys know who I’ll be rooting for this season on #dwts @iamvalc and @tamarbratonher I know you guys are gonna kill it!!” she captioned an image on Instagram as she posed with the dancing duo.

“Dancing With the Stars” airs Mondays at 8 p.m. EDT on ABC.