On Kendrick Lamar’s recent album, To Pimp a Butterfly, he dropped the following rhyme: “Critics want to mention that they miss when hip hop was rappin’ / M*********** if you did, then Killer Mike’d be platinum.” Well, the way Mike is carrying on as a member of rap duo Run the Jewels, he might well be going platinum soon. The group - completed by Brooklyn producer and MC El-P - had a huge 2014, with their second album, Run the Jewels 2, becoming a genuine crossover hit - discussed as much on taste-making blogs as it was in broadsheet newspapers.

They’re political, funny, smart and modern, yet their music is steeped in the traditions of hip hop, as a June mix featuring the likes of Public Enemy and Boogie Down Productions for Tom Ravenscroft on 6 Music proved. Both Killer Mike and El-P have long histories in rap music - Mike as an Outkast associate and critically acclaimed solo artist; El-P as member of Company Flow, boss of respected hip hop indie Definitive Jux as well as a solo artist with three albums under his belt. With Run the Jewels, though, they're both doing their best work, and for many rap fans this debut performance at Glastonbury is as significant as Kanye’s.