Chris Eubank Jr produces four knockdowns in points win over Liam Williams
Eubank is now looking to challenge for middleweight world honours next with Gennadiy Golovkin on his mind.
Chris Eubank Jr put down Liam Williams three times in the opening four rounds before going on to secure a unanimous points win in Cardiff.
Their middleweight grudge match - which took place at the Motorpoint Arena in front of 7,000 - had been rescheduled twice, because of an injury to Williams and then coronavirus restrictions.
There were plenty of words exchanged in the build-up, with Williams having to be spoken to by the British Boxing Board of Control after claiming he wanted to "kill" Eubank in one of his pre-fight interviews.
Eubank, who had suffered only two defeats in his 33-fight career, was cheered as he made his ring walk but soon silenced the raucous home crowd when he put Williams down during the opening round.
Williams was sent to the canvas again during the second by a left hook from Eubank.
The fight appeared set for an early finish after another knockdown for the 29-year-old Welshman in the next.
Eubank Jr is turning it on, Williams down for a third time! 💥#EubankJrWilliams | @Boxxer | @WassermanBoxing pic.twitter.com/5Jg4OYRjeq
— Sky Sports Boxing (@SkySportsBoxing) February 5, 2022
However, spurred on by the Cardiff support, Williams rallied in the sixth, with the referee having to keep the men apart as the contest drifted somewhat in the latter stages after such a fast start.
Eubank, 32, produced another telling blow in the 11th round to knock Williams down again to hammer home his domination on the judges' scorecards, which read 116-109, 116-108 and 117-109 in his favour.
"I wanted to teach this man a lesson. He had said some very menacing things to me leading up to this fight and I wanted to punish him," Eubank said on Sky Sports following his victory.
"I thought about it before I got in the right and thought, 'I don't even want to knock this guy out in the first round, I want to punish him, to teach him a lesson'.
"I want to get people like that out of boxing - you saw the fight, (there were) headbutts, head locks, all types of crazy stuff. I am surprised he didn't get disqualified.
"But I take it like a man and I punished him like I said I was going to do, it was a fun night."
Eubank added: "If I had stepped on the gas at any time in that fight he would have been gone and I didn't want to give him the easy way out.
"I wanted to let him know there are levels to the game and don't go out there being a big mouth to guys who you can get hurt against. He thought he was something he wasn't."
Shields and Marshall clash
On the undercard, Claressa Shields added the WBF middleweight crown to her WBA, WBC and IBF titles after a unanimous points win over Ema Kozin.
Shields' impressive display edged her closer to the prospect of a showdown with WBO champion Savannah Marshall.
The pair clashed after the fight with Marshall claiming Shields had put the fans to sleep during her first bout in the UK.
Shields - regarded as the greatest fighter in the female game - was forced away from Marshall as the war-of-words escalated.
Marshall will face Shields next - as long as she wins her upcoming title defence later this year.