The Donostia tournament in San Sebastian, Spain commemorates the centennial of the famous 1911 and slightly less famous 1912 tournaments held in that city. 1911 was Jose Capablanca's brilliant European debut, and he won the event over Akiba Rubinstein and many other notable players of the day; while 1912 saw Rubinstein take first place, half a point ahead of Aron Nimzowitsch and Rudolf Spielmann.
As you may recall, the 2011/2012 edition was characterized by the (near-)novelty of having opponents play both games of their mini-matches simultaneously, and to continue doing so in the rapid and blitz tie-break games if necessary. It was also quite strong, with (I believe) seven players rated over 2700 and several other former members of the club as well. There were seven knockout rounds, and after the first three the final 16 included the top 11 seeds.
It was at this point that they started to drop. Second seed Shakhriyar Mamedyarov lost 2-0 to Granda Zuniga, despite having the better position and a huge time advantage on both boards. Eleventh seed Andrei Volokitin defeated the fifth-seeded Arkadij Naiditsch, and in a very mild upset the ninth seed Viktor Laznicka defeated Maxime Vachier-Lagrave.
In round 5 the two upsets were Laznicka knocking off the top seeded Vugar Gashimov while Volokitin eliminated the third seed, Ruslan Ponomariov. That set up the semi-final matches Viktor Laznicka-Alexander Moiseenko (the fourth seed) and Leinier Dominguez (seventh seed)-Andrei Volokitin.
Once again, the underdogs won, and then Volokitin defeated Laznicka 2-0 in the final to take first place. This is probably the greatest success of his chess career thus far, and although the event wasn't rated I'm sure it will be a tremendous boost to his confidence and will hopefully push him over 2700 in the near future.