The 27-year-old tearfully celebrated his strike by pulling off his shirt to reveal a vest emblazoned with a picture of his father, Avi, who died last December after being involved in a motorcycle accident.
Gunners' gonners: Cohen (centre) heads home the 90th-minute winner
'Tamir has had such a difficult year,' said Coyle. 'He had an operation in the summer and by the time he was up and running, the lads were flying because we had a good start to the season.
Tribute: Cohen revealed an image of his late father
'He was on the brink of coming back in when his father passed away. Avi had actually spent a week with us at the training ground just before he passed away.
'When you got to know Avi, you couldn't help but become attached to him. I know it was emotional for Tamir but it was emotional for the lads as well.
Letter of the law: The gesture earned Cohen a booking from referee Mike Jones
'Tamir has a huge burden as his father (a former player for Liverpool) was such a huge name in Israel. For him to get that winner, I am delighted because it has been a traumatic year.'
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Explore more:People: Owen Coyle Places: Liverpool, Israel