With the Hammers getting two goals ahead, and then missing a penalty that would have restored that two goal cushion, only to draw 2-2 in the end, many feel it was the start of the side's problems at home or, at least, that a win that August day would have lifted the psychological spectre of a home hoodoo that has persisted throughout the season.
"We can't look back; there are lots of people in the club, and a lot of our supporters, that look back on the opportunity of taking three points on that day being missed as being part of our problems this year, because it would have been a home win," he says.
"But it wasn't; you can spend too much time looking back on what might have been, and you take your eye off the ball and lose your focus.
"Then you are forever making excuses, and we are not a team that makes excuses - and I am not a manager that makes excuses; I would rather live in the real world.
"I have never dwelt on the home game against Arsenal, and if anyone asks me about that game, I simply say it was a cracking performance by us.
"We had them fully stretched to go 2-0 in front, deservedly, and it took a world class strike from Thierry Henry to help get them back in it, and it is possibly a goal of the season.
"At 2-1 they had a fighting chance - and took it."
Glenn is hoping to avenge the memory of last season's defeat at Highbury, and he adds:
"We played very well, performed to our limit, and took them to 78 minutes before they could break us down.
"It was a game a lot of people remember for Fredi's 'goal' that never stood.
"The ball was clearly over the line and Ashley Cole, who is not playing on Sunday, hooked the ball back into play from behind the line.
"The linesman made an honest error, which anyone can make, and you can probably say he didn't have the best view anyway.
"But everyone in the ground could see that the ball had gone over the line.
"We fought hard that day, and it came back to us through Nigel Winterburn that Arsene Wenger was mightily impressed that we fought so hard - especially as we couldn't really go any higher and were safe from any relegation worries.
"I know privately he was impressed with our fighting spirit."
He knows the task will be no easier this time around and adds:
"Highbury, Old Trafford, Anfield - these are really tough places to go.
"I think the whole country saw Arsenal's performance last week against Birmingham, and I have got to say I thought they were sensational.
"You can't get away from it; everyone had an excellent game and they almost played machine-like in the way they interchanged with each other and the pace they showed throughout the team.
"It is a very tough game but, as always, whenever you go to Highbury, it is a game you must look forward to.
"We must go there with no fear; I always thought as a player that it is good to test yourself against the very best - and that phrase certainly applies to Arsenal over the last few seasons.
"They have got a wonderful squad and the manager has done an excellent job from the moment he took it up, full stop.
"Most of his buys have been excellent and you can go through the players that he has bought - Henry, Wiltord, Gilberto, Vieira, Edu, Pires, Ljungberg... but we mustn't be fearful.
"You have to go there with a determination and a belief that you can survive and come away with a good result.
"There won't be too many people outside our dressing room who will believe that we can go and get a result, but the resolve of the boys is there in the performances even if we have not being getting the results we deserve.
"It is those draws that we needed to turn into wins but, you have to be honest, you would very much take one of those draws this week.
"We have been beaten only once in seven, but unfortunately with just one win in the cup, and the rest have been draws where you only pick up a point at a time.
"But within those draws there have been games that should have been wins - though it is encouraging that there have been games where we have come from behind."
One of the lesser known Highbury players has a big fan in Glenn who reveals:
"I am very impressed with Toure who I think is going to be a terrific success at Highbury over the next few years; I am sure he will bed down and make a position in the team his own.
"It is a typical Arsene buy - powerful, strong quick, and he seems to be able to run all day.
"What I really like about him is that he plays with a lovely smile on his face and you don't always see that nowadays which is a shame.
"But when you see him he has that smile that says 'I so enjoy playing football and love being at Arsenal Football Club' - and that attitude, for me, is great."