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Manchester United manager David Moyes says he finds his club's start to the new season "hard to believe".
Among their first five Premier League games, the champions host Chelsea and Manchester City and Liverpool away.
Moyes said: "I find it hard to believe that's the way the balls came out of the bag, that's for sure."
The Premier League responded by saying: "We have absolutely assured him the process is random and above board. He has accepted those assurances."
A league spokesman also confirmed that Moyes had put his concerns to them directly.
However earlier on Thursday the Scotsman said: "I think it's the hardest start for 20 years that Manchester United have had.
"I hope it's not because Manchester United won the league quite comfortably last year [that] the fixtures have been made much more difficult."
Moyes officially took over from Sir Alex Ferguson, who retired after 26 trophy-laden years in charge, on 1 July. The former Everton boss saw his new side win the Charity Shield with a 2-0 victory against Wigan last week. They start their Premier League campaign away at Swansea, before facing Chelsea, Liverpool, Crystal Palace and Manchester City.
Manchester City, who finished second last season, play two promoted clubs, Hull and Cardiff.
Chelsea, meanwhile, will face two teams who finished in the bottom half last season as well as Hull, Everton and Man Utd.
Four of Arsenal's opening five opponents finished in the bottom half last season, although they do have the derby against Tottenham. Spurs also face two promoted teams as well as Swansea and Norwich.
Meanwhile, Moyes refused to be drawn on whether Wayne Rooney, who has been the subject of two bids from Chelsea, would feature in Saturday's season-opener at Swansea.
The striker, 27, missed Sunday's Community Shield win over Wigan with a shoulder injury but was fit enough to start England's international friendly victory over Scotland on Wednesday before being replaced by match-winner Rickie Lambert.
"It was great for Wayne to get fitness and he played for 65 minutes or so, so overall I was really pleased with the outcome," said Moyes, who was at the game to watch Rooney and his club-mates Danny Welbeck and Tom Cleverley.
"Hopefully when I get back to Old Trafford I will be able to tell you how he is and how his fitness is so. Until I assess that I can't say any more."