Southampton defender Kyle Walker-Peters admits defeat at West Ham is 'devastating'.
A win would've seen Saints move out of the bottom three.
"It's a game that you look at and think it's probably one of the most important games, so you know, really devastated," Walker-Peters told the club website.
I thought we played well and controlled the game but it's just that final end product that we need to improve on."
On Nayef Aguerd's winning goal, Walker-Peters continued: "It was a good delivery, good header, and we have to just defend it better, to be bluntly honest.
"Disappointed to concede from a set-piece when they had nothing. Every game in the Premier League is (about fine margins), every game is so tough.
The fine margins are the margins that count and unfortunately they didn't go in our favour today. We've got to take our chances when we get them and turn things around."
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