Savannah Marshall thinks Claressa Shields promises too much, delivers too little.

Marshall, the WBO women’s middleweight titlist from Newcastle, England, has been on a collision course with Flint, Michigan’s Shields, who holds the WBC, WBA, and IBF titles, for the past couple of years. The two signed deals with British broadcaster Sky last year with the idea that they would eventually meet in the ring, most likely later this year. Fueling their rivalry is the fact that Marshall has a win over Shields during their amateur days.

The 30-year-old Marshall, however, will have to do her part Saturday night against Femke Hermans of Belgium at Newcastle Arena in Newcastle in order to ensure her showdown with Shields will take place as planned.

Marshall and Shields have not been shy flinging verbal barbs at each other. They had a very public spat in February after Shields’ dominant, but admittedly uneventful, win over Ema Kozin at Motorpoint Arena in Cardiff, Wales. On the Sky broadcast, during Shield’s fight, the camera caught Marshall, who was sitting ringside, acting as if she was asleep. One of the few knocks on the credentialed Shields, a two-time Olympic Gold medalist and three-division champion, might be that she produces few stoppages inside the ring; the undefeated Shields has 12 wins but all but two of them went the distance. The undefeated Marshall, on the other hand, has 11 wins, nine of which came by knockout, although her résumé pales in comparison to Shield’s.

Marshall believes Shield’s ambitious pronouncements often fall flat because of her evident inability to truly put her opponents away early. Shields, 27, calls herself the GWOAT, or Greatest Woman of All Time, a nod to the famous reference originally linked to Muhammad Ali.

“Like I said, you can’t put that you’re the greatest, [that] you’re going to do this, you’re going to do that and then just not perform in that sense, can you really?” Marshall told BBC 5 Live Boxing. “Not taking that away from her. She’s a brilliant fighter, she’s never been beat. But you can’t say that you’re gonna do this and that and not do that really.”

Asked about their vitriolic encounter in February, Marshall offered some more details.

“A lot of it stemmed from standard Claressa’s talk,” Marshall said. “[She] would [insult] me on Twitter and in press conferences and interviews, then when [we encountered each other in person], she wanted a hug and fist bump and I was like no, it doesn’t work like that. It wasn’t just that.

"All week she was saying she was gonna knock us…out, do this and do that. Ramming and ramming ‘She’s the GWOAT’ down everyone’s throat all week.”

Marshall (11-0, 9 KOs) knows she needs to beat Hermans (12-3, 5 KOs) on Saturday so that her rivalry with Shields will actually play out inside the ring.  

“It’s all off me on Saturday night,” Marshall said. “So obviously I gotta get past Hermans. Then it’s basically a done deal. It’s all on me on Saturday.”