Groves won the vacant WBA 'super' super-middleweight title after a barrage of vicious punches stopped Chudinov on his feet in the sixth round.
Old rival Carl Froch, who dealt Groves two defeats in world title encounters, stood and applauded from his ringside commentary position at the fight's conclusion.
Groves had also been beaten by Badou Jack in America and Chudinov, his latest foe, immediately made it clear that he was not a soft touch with his performance in the early stages in Sheffield.
Groves was pushed onto the back foot in the opener as Chudinov, whose only previous defeat was to Felix Sturm who immediately failed a drugs test, marched forwards relentlessly. There was nothing pretty about the Russian's approach but his rigid, rugged style presented early problems.
An accidental head clash horribly cut Groves by the eye in the fourth round and, in the next period, the dripping blood appeared to cause issues. Suddenly, Groves whipped a right hook that stiffened the stance of Chudinov - a sign of things to come.
"You could make this easy," screamed his trainer Shane McGuigan, who Groves would later thank for "resurrecting" his career after three failed bids at world titles.
The 29-year-old Londoner's powerful punches began finding their home with more frequency in the sixth and, although Chudinov stood firm, Groves' barrage did not relent. After nearly a minute of unanswered punching, the referee called a halt.
"I'm usually a character who likes to be well rehearsed, but this time I've got no words," Groves said. "This is the end of a lifetime's work.
"Shane McGuigan has resurrected my career. Now I'm mature enough to admit that. I feel like I'm the best in the division - I'm willing and ready to fight anyone.
"He caught me with some good right hooks - one actually stung quite a bit. But I found my feet - I can put those losses to bed now, get on with my life and hopefully go on to better things."