Eurovision's voting often provides as much entertainment as the song contest itself, with colourful hosts and pithy commentary.
But now an apparent voting anomaly has left Russia complaining about an "outrageous incident".
Azerbaijan, a former Soviet republic, is trying to find out why the votes announced on the night did not give any points to Dina Garipova for her entry What If .
And Russia is investigating an alleged vote theft.
Russian foreign minister Sergey Lavrov met Azerbaijan's foreign minister Elmar Mammadyarov, who said the country's mobile phone operators reported Russia came second in the local vote, which would have given Dina 10 points.
She is also reported to have scored highly with the jury.
Mr Lavrov called it an "outrageous incident". He added: "When 10 points have been stolen from our participant it doesn't please you, particularly in the way the event is organised.
On the night Azerbaijan awarded its points to Ukraine (12), Georgia (10), Malta (8), Belarus (7), Romania (6) Denmark (5), Greece (4), Lithuania (3), Norway (2), Moldova (1).
Russia gave Azerbaijan a 12-point maximum.
With 39 countries taking part, Russia received points from 29 of them, with Malta, Romania, Greece, Italy, Norway, Austria, San Marino, Albania and Switzerland the other countries not to give them any points.
Russians take Eurovision very seriously and won in 2008 with Dima Bilan. This year's entry finished fifth overall on Saturday , 17 points behind fourth-placed Norway.
Azerbaijani television is investigating. It was unclear where any mistake or vote manipulation might have occurred.