Jennifer Lopez, Alex Rodriguez and Casper Smart: Dinner For Three?

When Jennifer Lopez and Alex Rodriguez went out for dinner on Monday night, they probably didn't expect to run into her ex ... but that's exactly what happened when Casper Smart showed up to the same dinner spot.

The couple went out for a romantic meal at Craig's in West Hollywood, arriving separately but leaving together by sneaking out the back. Keeping it casual in a navy jumpsuit, JLo led the way past photographers to their awaiting car once dinner was over.

Smart was seen going into the restaurant solo. It's unclear who Casper was meeting or whether he said "hi" to his ex and her beau once he was inside.

We do know Casper is tight with one of JLo's exes ... as in, ex-husband. Casper and Marc Anthony took a cute selfie together in November showing there's no bad blood between the two.

Hollywood ... it's a small town.

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