However, former Newcastle striker and the all time leading Premier League goal scorer Alan Shearer thinks that Mourinho's whinging is unwarranted, and his side will be a force to be reckoned with.
"Manchester United, you know the harmony isn't great there, but they've obviously got great players, a great manager".
"I told that during pre-season it looked like I was saying something absolutely out of order, something insane, I repeat and maybe tomorrow the reaction is the same: Pre-season hard when you don't have your players to work, as simple as that".
The move was created to ease disruption in the first few weeks of the campaign after a number of high-profile players including Alexis Sanchez, Philippe Coutinho and Virgil van Dijk missed matches at the start of last season due to transfer speculation.
The club says that the Welsh worldwide has resumed training but didn't reveal whether he will be available for selection against Manchester City.
Mauricio Pochettino wanted Jack Grealish, however, Aston Villa refused to sell.
"So, the pressure is on and there is even speculation he might not last much longer in his job".
Brazil worldwide Fred, highly-rated but raw full-back Diogo Dalot and third-choice goalkeeper Lee Grant all arrived at United by early July, but nobody followed despite Mourinho's explicit desire to bring in two more players.
"Tottenham haven't signed anybody".