Jay-Z Makes Surprise Appearance at Rihanna Concert

Rihanna thrilled fans at her concert last night at the Izod Center in East Rutherford, New Jersey by bringing out her mentor and frequent duet partner, Jay-Z.

As Rihanna sang the intro to 'Run This Town,' she threw up a diamond and the rapper popped up through a hole the stage, surrounded by a cloud of smoke. He stood almost motionless for a full minute, basking in the applause as the audience went nuts.

The pair performed 'Run This Town,' their collaboration with Kanye West, who just happened to show up at a Rihanna concert two days ago to perform the very same song. Jay stayed around to deliver his opening verse on the Grammy-winning smash hit, 'Umbrella,' before calling it a night.

A multiple nominee at this year's MTV Video Music Awards, Rihanna continues her Loud Tour this weekend with shows in Philadelphia in Boston.

Watch Jay-Z and Rihanna Perform 'Run This Town' Together