FULL STORY:  Ryan Reynolds better watch his back, because someone just drew a bead on him . . . and this someone has done HARD TIME.

During an interview last week, Martha Stewart had this to say about Ryan . . . quote, “You want to know something?  He’s not so funny in real life.  No, he’s not so funny.”

Ryan knew better than to step up to Martha, though. 

Responding to a Tweet about Martha’s comments, he said, quote, “I’d disagree with her.  But I tried that once.  The woman is unexpectedly spry.  She really closed the gap after a mile or so.”

But Hugh Jackman didn’t mind getting involved.  He replied, quote, “Finally someone says it.”

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