After her latest high profile 800m victory Mariya Savinova confirmed herself as the world's most improved performer and now undisputed No. 1 since placing fifth at the last Championships two years ago.
Caster Semenya on that occasion was a runaway winner and in fairness the defending champion did everything almost perfectly right to retain her gold medal in a whirlwind two laps of the Daegu 2011 track where all of the eight finalists finished in under two minutes.
But on this occasion it was Russia's Savinova who since that setback in Berlin's 1936 Olympic stadium has added the IAAF World Indoor, European Outdoor and Indoor titles to her collection of trophies and came out on top wining in the fastest time of her life of 1:55.87.
Semenya lowered her season's best to 1:56.35 - her second SB of the Championships - with Janeth Jepkosgei the Kenyan winner of the 2007 gold medal doing likewise when taking third in a blanket finish for the bronze medal.
Jepkosgei just held off US champion Alysia Johnson Montano by 0.06sec with a time of 1:57.42 both season's bests, while Ekaterina Kostetskaya the Russian girlfriend of Australia's Olympic Pole Vault champion Steve Hooker was also in the mix finishing in 1:58.42.
It was Jepkosgei who forced the pace over the first circuit powering through 200 in 26.61 and then passing the bell in 55.5 as the pack sped around the bend and down the backstraight with all of them still having the gold medal on their minds.
Then Semenya made a positive move and broke clear as she hit the front after 600 passed in 1:26.07 and increasing her space it seemed a second successive victory might be on the cards for her.
But Savinova 26, well down on the pace at the bell, was getting her act together and moved with purpose around the final bend where Semenya looking quite awesome was blowing away the challenge of a fading Jepkosgei.
It seemed the 20-year-old South African might hold on but her more compact rival, particularly her long striding legs, caught her 15 metres from the line to score another celebrated victory.
Semenya remaining upbeat despite the narrow loss, said: "The race was pretty good. Even though I got silver I really enjoyed it better than two years ago. I know I won gold in Berlin, but I am feeling much better today."
Savinova's clocking which improved her world lead and then personal best of 1:56.95 she posted at last month's Russian Championships, saw her become the first woman from her country to clinch the global crown since Liliya Nurutdinova won in the colours of what was then the Soviet Union 20 years ago in Tokyo.
David Martin for the IAAF