The Reds Head Coach spoke to the media after Barnsley were defeated in Extra-Time in the EFL Cup by Northampton Town.
With the scores level at 1-1 after 90 minutes, 30 minutes of extra-time were played which saw a 114th minute winner from Cobblers midfielder John-Joe O'Toole, who headed the winner from a corner.
On the defeat, the Reds Head Coach said, "It's a sickener, just the manner of the defeat. Obviously we were in control at 1-0 and playing well, but I thought we didn't have enough efforts on goal for how we dominated the ball. Second half we wanted to come out and do that but obviously the goal changed the game. You can't do anything about that, they got a lift from it but we played our way back in, but then we were wasteful in front of goal for the remainder of the game.
"We then gave a goal away with shocking marking from a corner in the dying minutes. It's all about being tight and not giving anything away in your box, then being ruthless in the opposition box. You don't deserve to win if you don't take your chances."
The Reds created multiple opportunities during the match but couldn't get the decisive second goal. Heckingbottom explained he was pleased that the team were creating chances, because if they weren't it would be a problem, but at the same time he felt his team should be scoring more.
After coming close to scoring on multiple occasions, Heckingbottom stated, "You get an 'ooo', but it's no good looking pretty or getting an 'ooo', if you score it's a different story."
Top goalscorer from last season Sam Winnall was injured in the defeat at Ipswich Town on Saturday, to which Heckingbottom gave an update on when he might return.
He said, "We're hopeful of having him back within a month. Games like this he would have loved to have been on there for those chances, that's for sure!"
The Reds will now play their first home Sky Bet Championship fixture of the season against Nigel Pearson's Derby on Saturday at Oakwell.
Watch full reaction from Paul Heckingbottom over on Barnsley Player HD.
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