Complex sentence: Before Rusev could leave with the championship, however, Reigns delivered a Superman Punch on Rusev, then declared he would give Rusev his rematch at the event in a Hell in a Cell match.
Split into simpler sentences: Before Rusev could leave with the championship, Reigns delivered a Superman Punch on Rusev. Reigns then declared he would give Rusev his rematch at the event in a Hell in a Cell match.