The Hammers kick off their third season at the former Olympic stadium against Bournemouth on Saturday with some fans still unconvinced about the move from their old Upton Park home.
Such was the ill-feeling last season that the home game against Burnley was marred by pitch invasions and anti-board protests.
Meanwhile, on the pitch West Ham have won just 14 of their 38 Premier League matches at the stadium.
But as Pellegrini prepares for his first match in the home dug-out he insists there is no reason the club cannot make a success of their surroundings.
“It is a stadium for a big team. West Ham is a big team,” said the Hammers boss.
“The Boleyn Ground was a great stadium with a lot of atmosphere. But it was for 30,000 people. The London Stadium is for 55,000, so 25,000 more fans are allowed to see the game. It is our home stadium because it is what this club needs and deserves.
“I don’t know why that stadium has to be difficult. I don’t see any reason why it has to be difficult.
“The pitch has the same measurements. The grass is in very good shape. The atmosphere, with 55,000 people, is great. The stadium is not an excuse.
“When a season finishes, it is is finished. All the experiences, positive or negative, must finish at the end of the season.
“Now we have a new season. I don’t know why it can be a negative stadium, there is not any reason.
“They changed from a stadium that was the club’s home for 100 years, that’s always a change. But it’s a positive change, not a negative change.”
Lucas Perez and Carlos Sanchez will be added to the West Ham squad.
The duo joined the Hammers on deadline day but were not involved in the 4-0 defeat at Liverpool on the opening day of the season.
Andy Carroll, Winston Reid and Manuel Lanzini remain long-term injury absentees but Pellegrini has an otherwise fully-fit squad.
Hazard has often sparkled in six years at Chelsea, bringing comparisons with Lionel Messi and Cristiano Ronaldo.
The Belgium playmaker could make his first start of the season in Saturday’s Premier League clash with Arsenal and will be expected to do well after a strong showing at the World Cup.
Sarri said: “We are talking about one of the most important players in Europe now but, in my opinion, he can improve more. He can be the first.
“It depends on him. The best for technical skill, the best for scoring, but I think it depends only on him. On his mind.”
The 27-year-old is beginning his seventh season at Chelsea and has twice won the Premier League title. He hinted after helping Belgium finish third at Russia 2018 that he was ready for a new challenge.
Rumours of a switch to Real Madrid have been persistent and have grown as Hazard has two years remaining on his current contract and has been deliberating over the offer of an extension for some time.
The Spanish transfer window remains open until August 31, but Sarri has no doubts Hazard will be with Chelsea for the rest of the season, despite the absence of Champions League football after the Blues’ fifth-placed finish in last season’s Premier League.
The Gunners travel to Chelsea on Saturday evening on the back of a 2-0 home defeat to reigning Premier League champions Manchester City in Emery’s first game in charge.
The Spaniard replaced Arsene Wenger in May and is attempting to introduce his own style and philosophy after more than two decades under the former manager.
Playing out from the back is one of those changes, as is encouraging his players to press across the pitch – demanding more from his forwards as he looks to defend from the front.
Ozil has come in for criticism for a drop in effort at times but, under Emery’s new system, Arsenal’s highest-paid player will be expected to muck in.
The former Real Madrid man endured a tough summer, culminating in his acrimonious retirement from international duty with Germany following a disappointing World Cup.
When asked about the defensive duties placed on Ozil in the City game, Emery replied: “Every player needs to (defend) in the true moment of a match.
“There are defensive moments and attacking moments. Every player each needs this commitment. For me, we need to start together, whether we are attacking or defending. I want that from every player.
“The position, he (Ozil) is playing all his career like a number 10-player, like a right-winger going inside to receive the ball.
“It’s clear he needs the ball more to give more options in the attacking moments. He needs to do (it) in each match, be demanding for us but defensive moments are for each and every player.”
Emery stuck with a tried and tested 4-2-3-1 formation against City but has hinted the system, as well as the personnel, could change until he finds the right formula.
“It depends on the performance and if the performance is good,” he said when asked about trying different systems.
“I want to give them the chances in each match and maybe we need a lot of matches for the chances for every player but we started with the pre-season and every player is playing for chances and minutes and with all the competitions.
“We only play Sunday, Sunday, Sunday but in September we will start playing Sunday and Thursday and also we are going to play more matches and I think every player will get chances to show us his performance for the team.”