American Shields holds three belts and Hartlepool's Marshall one going into the contest at The O2 in London. Both boast 12-0 professional records.
The pair have traded verbal blows ahead of the fight, with Shields as combative out of the ring as she is in it.
The 27-year-old from Michigan told Sky Sports: "This is my third undisputed match. I've actually been here before. I'm super excited for tomorrow. I'm going to get the job done.
"Talking don't win fights, boxing does. That's why I've got 12 world titles and she's got one.
"I'm a winner at all costs but I am going to drop Savannah Marshall tomorrow, I'm going to hurt her tomorrow and everybody who talks about all this punching power, it's not going to mean nothing tomorrow.
"She's got her little cheerleaders here. You're going to be crying tomorrow."
Marshall laughed off Shields' comments and spoke confidently of her own chances having handed the American the only defeat of her career as an amateur 10 years ago.
"Everything's been said now. It's all about tomorrow night and I cannot wait," said Marshall. "I made the weight easy, I always do. I'm feeling good. Five weeks has done me nothing but good. Let's get it on."
The fight was supposed to take place five weeks ago but was postponed following the death of the Queen.
There will be a historic all-female card featuring 22 women, with Shields and Marshall headlining and ticket sales booming.
"It's absolutely amazing," said Marshall. "The support has been unreal. I'd like to thank everyone who's bought a ticket. It means the world."