Lesnar began his attack on Monday while Rollins was in a match with Dolph Ziggler. As Rollins got ready to win the match using a Curb Stomp, The Beast suddenly arrived with his advocate Paul Heyman.
The champion, who was aided by Ziggler who held onto Rollins' leg, quickly took his rival to Suplex City before starting to deliver a number of F-5s that targeted Rollins' ribs.
Lesnar went on to give Rollins F-5s onto a steel chair set up in the middle of the ring that would continue to hurt the high-flyer's ribs. Heyman, after his client had delivered his third F-5 onto a chair, pleaded with Lesnar to stop the attack.
Rollins, backstage, was filmed being carted into an ambulance as he bled from the mouth and held onto his ribs. Lesnar wasn't through, however, stopping the ambulance from leaving so that he could continue his attack.
Lesnar dragged Rollins out the vehicle and delivered a final F-5 onto the stretcher. Lesnar defends his Universal Championship against Rollins at SummerSlam on Aug. 11.
The backstage moment had also featured Roman Reigns getting into a brutal brawl alongside his cousins The Usos against Samoa Joe and O.C. members Luke Gallows and Karl Anderson.
The brawl took place before the start of a scheduled Samoan Summit between Reigns and Joe that was set up so that they could settle their differences. The meeting turned into a huge melee that also eventually included Cedric Alexander helping out Reigns and Drew McIntyre joining Joe's side.
Alexander put it all on the line when he jumped onto everyone from atop the Raw LED board. Reigns and his team eventually won the fight with The Big Dog taking out Joe with a thunderous Spear.
Also on Raw, R-Truth kicked things off by defending his 24/7 Championship against Drake Maverick in a Mixed Tag Team match that also included Truth's friend Carmella and Maverick's wife Renee Michelle.
Truth won the match but was quickly pinned by a large number of WWE Superstars. Mike Kanellis made it out of the pile with the title in hand, making him the new 24/7 Champion. Mike quickly escaped the crowd of superstars and met back up with his pregnant wife Maria Kanellis.
Maria demanded that Mike lay down for her as she pinned her husband to become the new 24/7 Champion and the first-ever pregnant 24/7 Champion. Maria gloated around the locker room, daring anyone to try and fight a pregnant woman.
Other moments from Raw included Ricochet winning a Gauntlet Match to challenge AJ Styles for the United States Championship at SummerSlam; The Viking Raiders defeating Johnny James & Cole Carter; Raw Women's Champion Becky Lynch defeating Alexa Bliss and Nikki Cross before she was ambushed by Natalya; and Gallows and Anderson defeating The Usos and The Revival to become the new Raw Tag Team Champions.
The O.C., which also includes Styles, now has possession of the United States and Raw Tag Team Championships.