The Clarets were incensed by the intervantion of VAR and subsequent award of a spot kick from referee Kevin Friend, after Davinson Sanchez’s flick struck Ashley Barnes’ outstretched arm in the box.
Harry Kane took the penalty, after nigh on six minutes delay, and scored the only goal of the game.
But a number of mitigating factors were seemingly not looked at, with Barnes pulled by Sanchez seconds earlier, whether the touch off Barnes altered the flight of the ball significantly, and the distance between Sanchez and Barnes.
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However, Gallagher insists it was the letter of the law: "I was watching the game, when it occurred, I never gave it a second thought, the minute I saw one replay I said 'this will be a penalty', we've seen it all season, we might not like it, certainly teams don't like it when they're on the receiving end of it, but any player who puts his arm out like that, that high, and it strikes it, it's been a penalty all season.
"It strikes the arm, and it is clear and obvious, his arm is outstretched like that.
"Handballs are slightly different to fouls, a foul is a judgement decision, but handball is factual.
"The first question negates the second, if the arm is out like that and it hits it, which I think it does, the directives this season are if the arm is shoulder height or above and it strikes the arm, away from the body, which it did, a penalty is going to be given.”