Early career Pirog made his professional debut on 29 July 2005, scoring a sixth-round
technical knockout over fellow debutant Sasun Oganyan. On his fourth fight, he defeated
Sergey Tatevosyan to become the Russian national
middleweight champion. Tatevosyan was an experienced veteran and gave Pirog a tough fight, but Pirog's skills ultimately prevailed and he won a
unanimous decision 98–91, 98–93, and 97–95. From late 2007 to early 2010, Pirog won many regional and international
middleweight titles from both the
WBC and
WBO. as well as a very high
knockout percentage. Jacobs started the fight well and was ahead by 39–37 on all scorecards by round four. However, Pirog managed to hurt Jacobs with a right hand. In the fifth round of the fight, Pirog scored a major upset when he knocked Jacobs down with a hard right hand. Jacobs was unable to get back up and the referee waved off the fight, giving Pirog a knockout win and making him the new WBO middleweight champion. After the fight, Pirog said "After the second round, I knew I was good. I hurt him in the second and I knew I could come back and do it again." Pirog's exposure to worldwide audiences grew overnight, as the fight took place on
HBO pay-per-view as part of the undercard to
Juan Manuel Márquez vs. Juan Díaz II. However, in his subsequent two years as champion, Pirog only managed to make three defences, the last of which took place on 1 May 2012. In this fight, Pirog scored a wide unanimous decision, with scores of 120–108, 119–109, and 117–111, against
Nobuhiro Ishida.
Injury and retirement On 25 August 2012, Pirog was stripped of his title by the WBO after choosing to fight
WBA and
IBO middleweight champion
Gennady Golovkin instead of WBO
interim champion
Hassan N'Dam N'Jikam. During training for the Golovkin fight, Pirog suffered a serious back injury—a ruptured
disc—which forced cancellation of the fight. Several comeback attempts by Pirog to face Golovkin on an HBO pay-per-view main event were thwarted by ongoing back problems, effectively forcing his premature retirement. ==Personal life==