West Ham's final game at Upton Park was delayed by 45 minutes after the Manchester United team bus was pelted in a blockade by Hammers fans on Tuesday night.
Video footage shows the coach being struck by projectiles as it entered through the gates at the Boleyn Ground as throngs of home supporters gathered outside the stadium ahead of the historic occasion, with the east London club planning a post-match celebration.
The Red Devils requested for the kick-off time to be moved in order to give his squad sufficient time to prepare, and Hammers co-chairman David Sullivan was disappointed that the delay had been granted, while he denied that the opposition transport had come under attack.
"I'm gravely disappointed. It's more for our supporters. They have trains and buses. We have a wonderful, wonderful show after the match. Many fans will not be able to stay for that," Sullivan told Sky Sports.
"Man United should have got here at 4 p.m. They made the same mistake at Spurs. I'd make them kick off at 7:45 p.m [as scheduled]. The police have been kind to them."
He added on BBC radio: "There was congestion in the street, and they couldn't get the coach in. There were people around the coach, but there was no attack on the coach. If you check the coach, there won't be any damage to it."
United boss Louis van Gaal lamented the hostile reception and suggested it could affect his players on an important evening for the club's Champions League hopes.
"The images tell everything. I have seen also the police were taping," Van Gaal said after the incident.
"It is also a lot of emotions for people, but for us it is the second time in London we have to start later. It's better than last time because we have received our preparation time.
"It is not the first time I have seen that. It is not so nice. The way we have been received is not the proper way, of course. That makes all the influence on the players and that is a pity."
Red Devils captain Wayne Rooney added: "The coach got smashed up, but we'll just have to go and prepare and get on with our job.
"It's not for me to say, I'm sure you'll see. I'm sure West Ham will be disappointed with their fans."