Saints matched the hosts for long periods in the game after taking the lead in the first half, but a valuable lesson in seeing the contest through was given following Jamahl Hector-Ingram’s 90th minute winner at Little Heath.
“It’s hard and I feel for the lads as much as anything because it’s two weeks in a row now after the Christmas break where they’ve played well - as well as we’ve played all season - looked solid, got themselves in front and had chances to win the game, but individual mistakes cost us the game,” said Fleming.
“I think at 1-0 up if you’ve got chances to kill the game off, and we had a couple of half-chances, but two mistakes have cost us the game.
“We looked solid and we defended well which we’d worked tirelessly on in training but mistakes cost us. They are young kids and they are learning the game so it is part and parcel of that, but it’s happening too often and it’s hard to take.”
West Ham levelled with a deflected strike on the hour mark, while the last minute winner arrived shortly after Saints had an opportunity themselves at the other end of the pitch.
“The one thing is that technically we’re very good especially on the ball, which I noticed last year too when I came in, but that sense of danger and that defender’s instinct we need to try and get in them a little bit more. With four minutes to go, anything defensively you’ve got to play it safe,” the U18s coach highlighted.
“We were a minute into overtime and we had a free-kick at their end, and you think if the ball goes out you think the game is over, but we hit the first man and the ball was cleared. I think if we put the ball in a good area we’ve got a chance to win the game, but the ball is cleared and they’ve gone straight through and scored.
“I thought we were more solid and when I look through clips again and I look at the goals we’ve conceded this season as I’ve said, Chelsea apart we haven’t really been taken apart, it’s just been individual mistakes and calamities like it was today.
“I thought it was a very even game. We had the better of the first half and they had the second half, but it boils down to the individual bits.
“We want to win games and we want to do well, but it is about developing players and a massive part of their development is leaning how to win games.”