Simplify the following text for a Grade 9 native English-speaking person.
Original: At WWE 's August pay-per-view ( PPV ) event SummerSlam , Cena successfully defended the championship against Orton , and the following night on Raw , one of WWE 's primary television programs , Orton interfered in Cena 's match with King Booker and cost him the match .
Simplified: The feud began in July after Orton was named the number one contender for Cena 's WWE Championship . At SummerSlam , Cena won against Orton , while at Unforgiven , Orton beat Cena by disqualification .