While defender Luke Shaw could return at Everton on Sunday after three months out, there are several other long-term absentees.

Casemiro and Lisandro Martinez are not expected back until the new year while Jonny Evans is a few weeks away.

Ten Hag revealed United have looked into the reasons they have been so badly this term.

The former Ajax coach said: “We did some research and what you see is that the standards in the Premier League, this season and last season, have increased.

“I’m talking about the running stats, the intensity — the volume has increased.  Every time it’s a survival of the fittest and it’s a big factor in English football.

“Tactics, mentally always huge, but the foundation is always running and when you can’t run you can’t win games in the Premier League.

“Here you have the best players in the world — in the last couple of years the English clubs have taken the best players.

“Every team has very good quality and don’t have weaknesses, so you have to match their high standards and if you don’t, you drop off.

Lisandro Martinez is one of 14 United players on the treatment table Credit: Getty

“When the injured players are back, the quality will rise but we have others who can help us win games. That’s why we have a squad.”

Christian Eriksen is also some way from full fitness and striker   Rasmus Hojlund faces a fitness test before the Toffees clash.

The Denmark duo were injured in the 1-0 win over Luton before the international break.

And Ten Hag added: “Christian will take a little bit longer. It will take some weeks until he returns.

“Rasmus Hojlund, not too bad. Everton will be a close finish but we’re working on that.

“We’re not sure if he can make that but, hopefully, in the next week, he will return to the squad.”

United are — according to results — the Prem’s form team, having won four of their last five matches but they face a testing week.

After Everton comes Wednesday’s Champions League clash at Galatasaray then a trip to Newcastle.

Ten Hag believes the Premier League is a ‘survival of the fittest’ Credit: Getty

Goodison is also sure to be hostile with the Toffees still smarting from their ten-point deduction over a breach of financial rules.

Asked if they could be travelling to Merseyside at a better time, Ten Hag said: “That’s definitely the case  but we can’t do anything about it.

“You have to take it like it is. They will get more fuel. But it could work against them too.

“It’s about us — we have to focus on the game, our way of playing. We have to start with the right attitude.”

United’s mini-revival in the Prem puts them just five points behind fourth-placed Tottenham. And the most optimistic fans may point out they are only seven off leaders City.

Ten Hag added: “It was a tough start but I think we’re catching up.

“Now we hope we can stay with the same line-up — or the same 12 to 14 players — as so far that has been the difficulty. There is more to come but we are progressing.”