Jennifer Aniston and John Mayer Photo by: BAUER-GRIFFIN
Jennifer Aniston Waits Backstage at Mayer Concert | Jennifer Aniston, John Mayer
Jennifer Aniston and John Mayer continued to keep their romance firmly off the radar Saturday.

Slipping unnoticed into the musician's backstage area at the Hard Rock Calling festival in London's Hyde Park, Aniston stood quietly in the wings while the singer ran through a 45-minute set in front of an audience of ten of thousands.

But the actress wasn't just there to lend moral support: wearing a black-and-white floral halter-neck top and faded flared jeans, Aniston busily snapped away with her camera to record Mayer's on-stage performance.

It was the second time in two days that Aniston had joined Mayer for one of his gigs. On Friday, she took a seat in the upper level of the gritty south London venue, the Brixton Academy, before leaving with Mayer at around 11:30 p.m.

Earlier this week, the couple united in Amsterdam, where she was promoting the upcoming Marley and Me (with Owen Wilson) and Mayer was performing.

In keeping with the low-key theme of her London visit, she never once ventured into the Hard Rock VIP area and quietly left the show without anyone noticing.

Even the paparazzi camped outside her London hotel were left guessing.

Mayer later appeared on stage at the end of the show alongside headliner Eric Clapton and Aniston's close friend Sheryl Crow. But, again, Aniston was absent.
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