Jon Stewart did more than just host WWE SummerSlam.

Stewart was picked to preside over World Wrestling Entertainment’s second-biggest annual event Sunday night at Barclays Center in Brooklyn, N.Y. The former host of “The Daily Show” used the unique opportunity to help former enemy Seth Rollins defeat John Cena to retain the WWE World Heavyweight title and win the United States title.

Cena and Rollins had a great match in front of an energetic crowd. Cena looked poised to win the bout and a record-tying 16th World Heavyweight title, but he knocked out the referee during his finisher, at which point Stewart ran down to the ring with a chair and interfered.

It was reasonable to think Stewart was there to help Cena given his history with Rollins. The comedian/TV star surprised everyone and attacked Cena, though. He jammed a chair into Cena’s stomach and threw it down onto the mat for Rollins to complete a match-ending Pedigree.

Stephen Amell, star of the hit TV series “Arrow,” left his mark earlier in the night, too. But it hardly compared to Stewart’s antics, which were shocking, to say the least.