A wee bit jealous are we?

performance in Hyde Park last weekend was supposed to be fun, but unfortunately one little factor kept Ms. Aniston off the ‘happy train.’

While watching her man warm up for the gig with a brief run through, the Marley & Me star happened to notice that Mayer’s former flame - was attempting to sneak into the event.

That’s when the claws came out!

“Jennifer spotted Kimberly and asked John what she was doing there,” a witness told the Daily Mirror. “Jennifer doesn’t want anyone around who reminds her that he used to be a player.”

Let’s hope “used to” still remains in the past-tense.

Being protective of Aniston’s feelings, John promptly instructed his bouncers to eject Stewart from the premises.

Needles to say, it didn’t go over so well.

 “She had been told twice by security that she would be removed but she stood there bold as brass,” the previously mentioned source commented. “John told his bouncers to get rid of her at all costs. Kim was pulled off the stage and escorted [out], shouting: ‘Why doesn’t he want me here? Is this because of her?’ She totally embarrassed herself, but Jen looked relieved.”

Kudos to Aniston for standing her ground, what the hell was Mayer’s ex even doing there anyway? Trying to tempt him perhaps