Nicole Scherzinger and Derek Hough, who were partners for Dancing with the Stars' tenth season and ultimately won the mirrorball trophy, are reportedly dating.

"Ever since Nicole broke up with [race-car driver Lewis Hamilton], she's been hanging out with Derek," a source told Life & Style.

"He 100 percent acts like he's her boyfriend."

While Hough just recently split from former The Hills and Laguna Beach star Lauren Conrad after three months of dating, he reportedly wasn't hesitant to show off his new relationship with Scherzinger -- who is currently a judge on Fox's The X Factor -- in front of his ex-girlfriend at a club opening in Los Angeles on November 10.

"He didn't leave Nicole's side," another source told Life & Style. "Lauren tried her best to avoid him."

If the report is accurate, it won't be the first time Hough has dated a Dancing with the Stars celebrity partner. Hough and his sixth-season partner Shannon Elizabeth began dating during their Spring 2008 Dancing with the Stars partnership, which included the two being photographed kissing and canoodling on a Malibu beach but playing coy about the nature of their relationship -- even after they were the seventh couple eliminated. 

They subsequently confirmed their relationship in July before Elizabeth quickly squelched rumors that she and the three-time Dancing with the Stars champion were engaged and moved in together in October. However, the couple broke up in August 2009.