Former Arsenal forward Paul Merson has claimed that Erik ten Hag is taking on 'the toughest job of his life', with the Dutchman officially starting work as Manchester United head coach.
Ten Hag led his new side's first training session of the summer on Monday, with at least 17 players reporting for duty at the club's Carrington base.
Ten Hag has arrived at Man United off the back of leading Ajax to last season's Dutch title, and Merson has claimed that the Dutchman is moving to "the biggest club in the world" during a period when they are in "disarray".
"If Ten Hag managed for the rest of his life, it'll never be harder than what he's taking on now," Merson told Sky Sports News. "This is a massive job. It's the biggest club in the world and he is taking over when they're in disarray."
Ten Hag will be tasked with eventually challenging the likes of Manchester City and Liverpool for the Premier League title, but Man United finished sixth last season, and Merson has claimed that "at least three or four players" will be required to even battle for a return to the top four.
"He needs to bring in as many players as he can because this team is not going to get you in the top four. They need to bring certain players in - (Frenkie) De Jong at Barcelona, he's a good footballer - and then you move on from there. They need at least three or four players just to make a challenge for fourth place," he added.
Ten Hag is also believed to want a new centre-back, another midfielder, a wide forward and a striker during this summer's transfer window, while a new goalkeeper is likely to arrive if Dean Henderson departs.
"Antony, for instance, is worth £80m in the eyes of Ajax. The prices they are asking for are absolutely huge because they have no need to sell. They know Man United, like many clubs in Europe at this moment, need players. So it's a very awkward position Manchester United are in at the moment," Dutch journalist Marcel van der Kraan told Sky Sports News.
"Antony, he (Ten Hag) thinks is a great player but he knows he is too expensive at this moment, and that Frenkie de Jong is much more of an important player for him than Antony."
Man United's summer budget is allegedly only £100m, although the owners would be prepared to add to the amount if players left the club in the coming weeks.
The Red Devils finished sixth in the Premier League last term, some 13 points behind fourth-placed Tottenham Hotspur, while they were 35 points behind the champions Man City.
Man United also failed to impress in their domestic cup competitions last term, exiting the FA Cup in the fourth round and EFL Cup in the third round, while they were knocked out by Atletico Madrid in the last-16 stage of the Champions League.