Nigel Benn. World middle title in America. Barkley World super-middle title in Italy. Eubank II McClellan won all those fights with shocking ability when betting underdog
A honorary shout out to Badou Jack: Stevenson(D) DeGale(D) Dirrell Groves The other two times Jack was the underdog, he lost to Pascal and Browne.
Steve Robinson. He came in as a last minute replacement for a fight for the WBO featherweight title against John Davidson with a 13-9-1 record he was a journeymen who upset the odds to become a world champion. He was also the underdog vs Colin McMilan who was the former champion who lost the belt while ahead when dislocating his shoulder, but he won that one too. Paul Hodkinson was also favourite to beat him as he was more proven on the world level being the former WBC champion yet Robinson retired him with a 12th round KO. Duke McKenzie was a 3 weight world champion looking to make it 4 and was seen as the best Robinson would have fought up to that point and again Robinson upset the odds and came out victorious.
Yes, if looking from numbers in fight record. I usually look in resume deeper and for me upset was not his win via Ekimov but fact : he won via UD. I had assumed, if he will won, then only with stoppage, Ekimov was like too good boxer for him to outbox. Nieslen vs Bolotņiks : really surprised his good performance vs Nielsen.
The Nielsen match was actually the main reason I went with Bolotniks for the upset over Ekimov, but yeah, like you, I predicted stoppage, and if not that, maybe a lucky MD, but he dominated him so thoroughly that didn't leave the judges with any other choice.