Credit: Michael Rozman/Warner Bros.

Wedding bells could be ringing soon for Common and Serena Williams.

When Ellen DeGeneres asks the Just Wright (out Friday) star if he'll say "I Do" to his tennis pro girlfriend, 28, he says, "I definitely want to get married. I would love to get married and have kids."

Common, 38, (real name: Lonnie Rashied Lynn, Jr.) says his relationship with Williams started out friendly and grew more serious.

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"Actually, Serena and I have been close for about two years. It's been evolving," he tells DeGeneres in an episode of her talk show to air Thursday.

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He admits he's "emotionally involved" watching Williams on the tennis court.

"I sit there, and I'm just tense... and people try and talk to me, and I tell them to be quiet," he says. "I was sitting next to Richard Branson and I didn't pay attention. I don't care who is there. I'm focused on this tennis match."