According to The Wrestling Observer, there is concern within WWE that CM Punk might be more injured than he is letting on, and that it might affect his post-WrestleMania status. There have also been claims made that Punk is creatively frustrated with WWE and that he is burnt out.
As a result of one or all of the above claims, WWE is booking both The Rock and Brock Lesnar for the Extreme Rules PPV this year as it's likely Punk will be missing the event to take some time off. There was previous confusion that WWE planned The Rock vs Brock Lesnar for Extreme Rules, however that is not the case, as both men are simply being booked to appear at the show. No word yet as to who the two men might face at the PPV.