Ken Hamlin -- a football safety for the Dallas Cowboys -- is surprised Tony Romo dumped Jessica Simpson on July 9, the eve of her 29th birthday.

"I was shocked, but there is a reason for everything, and you never know what is going to happen," Hamlin told Usmagazine.com Monday at the Sports Dream Celebrity Poker and Pool Party in Los Angeles.

"His personal life is his personal life," Hamlin added. "I don't know what's going on."

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Even though ardent Cowboys fans accused Simpson, 29, of bringing bad luck to Romo's football performance, Hamlin told Us the singer "was a good person and a good friend."

"I didn't give her no flack," he told Us. "Every time I met her, I had nothing negative to say about her. She did a good job." A source told Us Monday that Simpson and Romo's split had "been a long time coming."

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Added another, "They go from one fight right into another, without a second break. It's always something with Jessica." On Monday - the day Us confirmed the split - Romo hit Hollywood's Key Club with some pals.

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impson, meanwhile, has been laying low. She is "doing OK," a third source told Us, but noted that she canceled her Ken and Barbie-themed birthday party because of the breakup.

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On Sunday, she took to Twitter to post a positive, post-split message: "Everyone needs to know that hope floats ... grab the strings and pull it back to you. Falling asleep with my mom and the dogs. Please lord give all of my beautiful fans, friends, enemies, and family rest. Bring all of us peace."

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