The 40 year-old, who lost to Lennox Lewis for the unified titles in 2000, went down by a similar margin to the rangy Belarussian as the judges came back with cards of 119-108, 119-109 and 119-110 respectively.
The enigmatic ‘Tuaman’ was gracious enough to talk with the media in his native country following what was only his fifth loss in 59 contests and seems ready to move on after initially retiring for two years in 2007.
“I did the best I could,” Tua told the Claudelands Arena crowd. “I actually got myself into great shape, because I believed I could do this and I believed that the fire still burns.
“But sad to say, my heart’s not in it any more – it’s time for me to try something else. There will be two people at home right now who will be happy with this decision – my mum and dad.
“That’s it for David Tua. I’d like to thank the public of New Zealand for their support and the people of the Pacific – your support has been absolutely ‘O for Orsome (awesome)’ from day one.
“David Tua left the building tonight. Thank you very much and God bless.”
Ustinov, 36, can look forward to some bigger challenges in the back of his latest win after Tua was rumoured to be lined up to face Wladimir Klitschko in 2014 before this weekend’s disappointment.
The Minsk-based puncher has now won two in a row since his solitary loss to Kubrat Pulev a year ago and may be just one or two fights away from a first world title shot after picking up a fringe WBA belt against Tua.
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