Lynch was a given a choice between facing either Smackdown Women's Champion Asuka for a second time or her rival, Raw Women's Champion Ronda Rousey.
Lynch chose Rousey after The Baddest Woman on the Planet successfully defended her title against Bayley in an open challenge.
Rousey, despite having to deal with injuries she sustained while battling Bayley's tag team partner Sasha Banks on Sunday, won the match after she slammed The Huggable One from the top turn buckle and immediately applied her Armbar submission hold.
"At WrestleMania I am going to break your mystique. I am going to take your title and I'm gonna kick your ass in front of the whole world," Lynch said to Rousey during an intense confrontation.
"How long have you been The Man Becky? Because I've been a household name for a decade," Rousey said in response. "Any ring I step into is mine. I own the ground under my feet and I'm going to own you at WrestleMania."
Lynch and Rousey will collide at WrestleMania 35 on April 7.
Rollins, who defeated Dean Ambrose to kick off the show, was given until the end of the night to make his decision by Triple H.
Lesnar and his advocate Paul Heyman, came to the ring to hear Rollins' decision with Heyman strongly advising that The Kingslayer not chose to take on The Beast unless he wanted to lose.
Rollins arrived onto the scene and without saying a word, immediately started to punch Lesnar. The champion withstood the assault and then decimated Rollins by delivering six F-5's in a row as Raw went off the air.
Other moments from Raw included Nia Jax and Tamina defeating Alexa Bliss and Mickie James to qualify for the Women's Tag Team Championship Elimination Chamber match; Baron Corbin defeating Kurt Angle; Intercontinental Champion Bobby Lashley confronting Finn Balor; The Revival defeating Zack Ryder and Curt Hawkins; Elias bashing Jeff Jarrett and Road Dogg with guitars; Liv Morgan and Sarah Logan defeating Natalya and Dana Brooke to qualify for the Women's Tag Team Elimination Chamber match; Braun Strowman defeating Drew McIntyre; and Jax punching Ambrose out of the ring.
Ambrose, after losing to Rollins, started to give a speech before he was interrupted by Jax and Tamina who had arrived for their match. The confrontation with Ambrose comes after Jax had inserted herself into the Men's Royal Rumble match on Sunday.