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Cameron Diaz recently brushed off the institution of marriage, explaining, "If I try to lock something down, I'm missing out on all the possibilities of what it could be."

But rumors are suddenly a-flying that she did try to lock something down with Alex Rodriguez and got cut loose as a result.

"For a long time, Alex thought she was a ton of fun," an insider alleges to Life & Style. "And because she kept saying that she never wanted to get married and have kids, he thought she would be an easy girlfriend. But then she pushed for more of a commitment, and he told her to cool it."

Another source pipes in that the actress, 38, feels "hurt and betrayed" by the New York Yankees slugger "because she tried so hard to please him. She traveled for him. … She went overboard."

Last month, A-Rod's camp moved quickly to deny an In Touch report that he was encouraging the lately bulging-bicepped A-lister to get a boob job, an enhancement she was purportedly willing to undergo.

Cam, who has been in London filming "Gambit" with Colin Firth, is now supposedly "secretly mourning the end of her relationship," which began with a bump-and-grind session at a 2010 Super Bowl bash in Miami.

A rift reportedly formed last October, but by this year's Super Bowl, they were once again tight, with the actress caught on camera hand-feeding A-Rod popcorn.

"Cameron told Alex in February that she was going to London to film 'Gambit,'" a mole tells the tab. "When he said it was a good idea because baseball season was coming, she was devastated."

So, are the hard-bodied lovebirds kaput?

Diaz's rep didn't respond to our request for comment on the breakup chatter, but a Rodriguez confidant dismisses the split speculation to Gossip Cop, insisting it's "not true."


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