The teenager, a gold medal winner at the 2014 World Junior Championships, produced a series of superb performances leading to a nail-biting 13-12 semi-final victory over Croatian rival Matea Jelic.

But the best was yet to come in a final against Turkey's Nur Tatar, the reigning world and Olympic silver medallist who claimed European gold in 2012.

Williams, adapting effortlessly to the senior ranks after recovering from two ankle operations, dispatched her 23-year-old opponent 4-3 to become the second Welsh champion in successive days after Jade Jones' under 57kg victory yesterday.

"I didn't expect a medal, let alone gold," she told BBC Sport afterwards.

"I can't even explain it, I'm just overwhelmed.

"I've just come back from injury so it's my second competition [and] to win a major it's insane, I can't explain it."

Her performance was even more remarkable considering the quality of her fellow podium finishers, as Jelic shared bronze with 2013 world champion Haby Niaré of France.

Williams is still unlikely to compete at Rio 2016, as Britain have secured their two women's spots in the under 57kg and over 67kg division where Jones and world champion Bianca Walkden are poised to participate.

Azerbaijan's Iranian-born European Games champion Milad Beigi Harchegani was among other winners today.

He beat another Turk in Yunus Sari in the under 80kg final as Briton-turned Moldovan Aaron Cook shared bronze with Poland's Piotr Pazinski.

Portugal's Julio Ferreira claimed under 74kg spoils after beating Croatia's Toni Kanaet in the final.

Nicholas Corten of Belgium and Claudio Treviso of Italy shared bronze.

But there was some Turkish success as Irem Yaman beat France's Magda Wiet-Henin in the under 62kg final.

Daniela Rotolo claimed another Italian bronze, while Rabia Gulec of Germany also secured a podium finish.