Evan Agostini / Invision/AP 1 / 14
Evan Agostini / Invision/AP 1 / 14

Last week, Will Smith and Jada Pinkett Smith shot down a tabloid report that they were ending their 14-year marriage and that Pinkett Smith had an affair with Marc Anthony, her love interest on TV's "HawthoRNe."

PHOTOS: Stars who hooked up on set

But although Pinkett Smith 39, and Anthony, 42, never had a full-blown romantic affair, one source tells Us the twosome had an "inappropriately close" friendship.

"They were a little touchy and like they were in their own little world," a set source explains, adding that the twosome often hung out alone in his trailer, and talked and texted frequently.

PHOTOS: Jennifer Lopez's romantic history -- and how she changed for her men

And when Anthony's own seven-year marriage to Jennifer Lopez began to fall apart, he leaned on his work pal.

"The more distant Marc and Jennifer became, the closer he got to Jada," a family insider says, adding that Pinkett Smith may have "overstepped her bounds" in lending Anthony marital advice.

"Jennifer didn't like that."

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