Borussia Dortmund midfielder Nuri Sahin has revealed his frustration after his side fell to a 2-1 defeat to Hertha Berlin in the Bundesliga on Saturday.
Although Dortmund took an early lead, they were unable to convert any of their chances and eventually let Hertha back into the game.
"We need more of a killer instinct to win these types of matches," the Turkey international is quoted as saying on the Bundesliga's official website.
"Had we scored the second goal, Hertha wouldn't have got back into the match. We should have added to our lead after going in front, but we took our foot off the gas.
"They defended well in the second half and took advantage of our errors in the first. We're very frustrated."
Dortmund are 12 points behind league leaders Bayern Munich in third place.