Alan Irvine was left to rue moments of defensive sloppiness from West Ham United as they exited the Carabao Cup to Everton on Wednesday night.
The Hammers recovered well from falling behind to Dominic Calvert-Lewin's early opener at Goodison Park and drew level thanks to Robert Snodgrass' fine strike right at the start of the second period.
At that point, Irvine felt the Hammers were well placed for a tilt at earning a quarter-final slot, only for Everton to add three goals without reply - and the assistant manager said they could have dealt with all three situations better.
The Hammers also twice came close to levelling again at 2-1, first when Manuel Lanzini slid wide of the target, then when Sebastien Haller forced a sharp reaction stop from Jordan Pickford with an acrobatic volley, to add to the feeling of what might have been.
"We got to a position where I was quite comfortable [after the equaliser]," Irvine said. "We obviously then conceded a poor second goal - we allowed Richarlison to come inside which is where we know he prefers to go, and then the deflection has made it very difficult for Darren, but we shouldn’t have let him come inside so easily in the first place.
"Then there’s a big moment when Seb Haller had the fantastic overhead kick which was saved, so we felt we were certainly in the game at that point.
"But again, another bit of poor defending led to the third goal, We had opportunities to clear the ball, which we didn’t do, and we were second in terms of following in when the ball hit the post too.
"That made it difficult for us and of course the fourth goal was even more disappointing. Once again we didn’t defend well on the edge of our box, and it’s ended up being a 4-1 and I don’t think that’s a reflection of the game. I felt the game was an awful lot tighter than that."
The Hammers again made full use of their squad at Goodison Park, keeping faith with the majority of the side which earned their fourth round slot by making eight changes from the team which defeated Wolverhampton Wanderers on Sunday.
Irvine explained that it was important that group were given the chance to shine against a fellow Premier League side, while also staying mindful of the need to keep his players fresh for the challenge posed by Leicester City this coming weekend.
We wanted to come here and get into the quarter-finals, and had we done a couple of our defensive jobs better we could have been doing that
Alan Irvine
He explained: "First of all, the boys who were playing tonight, a lot of them had done extremely well in the previous two rounds and thoroughly deserved their opportunity to play in a game where people can judge them against Premier League opposition.
"Maybe don’t get as much credit [as they deserved] for their performances against those League One sides that so it was important they had the opportunity to play.
"That was part of it, and obviously we do have to be mindful that we do have another hard game at the weekend, so there are certain players that we have to look after.
"Our job now is to pick everybody back up, and we played an eleven today which could be a team that plays in the Premier League. The players we picked were all players who have Premier League experience.
"It wasn’t as if we weren’t going into this game in a serious manner, we wanted to come here and get into the quarter-finals. There’s no question about that, and had we done a couple of our defensive jobs better we could have been doing that."