Olympic taekwondo champion Joel Gonzalez Bonilla has admitted that he was taken by surprise as Azerbaijan's Aykhan Taghizade knocked him out at the -68kg event in Baku.
The London 2012 gold medallist, from Spain, lost 7-5 in the quarter-finals of the tournament, the stage at which Great Britain's Martin Stamper also left the competition.
Gonzalez Bonilla told reporters: "In sport, there is always a loser and a winner at the end, and I'm disappointed that it was me losing today. They only thing I can do now is to come back stronger for the next competition.
"It was a very difficult bout today. I felt quite good today actually, but he caught me off guard."
Taghizade went on to beat Russia's Alexey Denisenko in the semi-final, and will face Karol Robak in the final later this afternoon.