With CM Punk expected to be back with WWE this summer, the writing team is currently working on different storyline plans for his return. One scenario being discussed is for Punk to be paired with Brock Lesnar upon his return, with Heyman and Lesnar eventually turning on him. Punk would turn and feud with a heel Brock Lesnar this fall.
Source: http://www.sescoops.com/storyline-plans-for-cm-punk-brock-lesnar-mick-foley-interview/80094
A CM Punk and Brock feud at SummerSlam! AND CM PUNK TURNING FACE HOPEFUL THAT MAKE AN ANTI HERO FACE!