Jay-Z made a surprise appearance at protégé Rihanna’s concert in New Jersey last night (July 21).

The rap superstar joined the flame-haired singer for a performance of their hit single ‘Run This Town’, which featured on his 2009 album, ‘The Blueprint 3’.

Before the show, Rihanna paid tribute to a fan killed in a car accident. She tweeted: “One of my biggest Rihanna Navy fans died today in a car accident!!! Gone but never Ever forgotten!!!! She was only 17 #DearKaren.”

The fan is thought to have been listening to Rihanna’s album, 'Rated R' when the car crash occurred.

Watch Jay-Z and Rihanna's live collaboration on 'Run This Town' during her recent concert here: