Claressa Shields turned in the kind of performance that not even her opponent can object to.

The Flint, Michigan, native and two-time Olympic gold medalist became the undisputed champion of the middleweight division a second time last Saturday at the O2 in London, when she ousted longtime rival Savannah Shields via unanimous decision over 10 rounds in their WBO, WBA, IBF, and WBC women’s 160-pound title unification fight. Shields has also achieved the undisputed distinction at junior middleweight.

Marshall, Hartlepool, England, had the distinction of being the only to own a win (in the amateurs) over Shields in either the unpaid ranks or the professionals, but she was no match for the self-declared “GWOAT.”

“It was a tough fight, I dug deep, but I thought the right woman won, yeah,” Marshall told BBC 5 Live Boxing. “I thought it was close.”

Marshall said she expected Shields to be quicker inside the ring and thought she was getting to Shields late with her right cross — in the end, Marshall knew she had come up short.

“I thought — obviously it’s different when you’re in there but I thought I was catching her with  the cleaner shots, kept catching her with the back hand at the end of the rounds,” Marshall said. “I thought she would’ve been faster. But she’s a brilliant fighter, she’s a brilliant fighter. Can’t take anything away from her. And like I said, the right woman won tonight.”

Scores were 97-93 and 96-94 twice, in favor of Shields. Peter Fury, the trainer of Marshall, has insisted that the fight could have gone “either way” and objected to the 97-93 scorecard, calling it “ridiculous.

Shields-Marshall capped a successful night of boxing in London. The undercard featured a competitive women’s 130-pound title unification bout between Americans Mikaela Mayer and Alycia Baumgardner. The latter ended up winning narrowly on points to unify the IBF, IBO, WBO, and WBC titles.