Erik ten Hag has warned his Manchester United players to accept being dropped from the matchday squad and that they must remain motivated to contribute when required.

The manager left Jadon Sancho out of last September’s trip to Arsenal, causing the player to challenge the decision publicly. The situation led to Sancho’s departure to Borussia Dortmund on loan, although he is now back in Ten Hag’s plans. The 24-year-old was left out of the 1-0 opening day win over Fulham because of an ear infection, Ten Hag explained after the game.

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On Thursday, Ten Hag was asked if Sancho was available for Saturday’s visit to Brighton for the early kick-off. “We will see,” said the Dutchman. “We have a squad and I hope we will have a squad with double positioning and when we go into the season after 1 September, that means also you can’t select all the players for a game.

“ But you need them all throughout the season because this season will be the survival of the fittest. The attitude of the players is very important, sometimes they will be disappointed, but they have to deal with it. You don’t win with 11 [players], you win with a squad. The prizes are decided next May and until then we need all the players in the squad and highly motivated to contribute.

“That is not an expectation, that is a demand from the club and from me as manager of the squad. The team is always more important than any one individual.”

Ten Hag hopes to sign Paris Saint-Germain’s Manuel Ugarte before the summer window closes next Friday. United’s preference is to buy the defensive midfielder but view the French club’s £51m valuation as too high, so a loan move is also being explored. The manager would not be drawn on this or any other potential deal.

“Be patient, sit, wait, keep working very hard,” Ten Hag said. “We will always try to make the best squad possible. We have a couple of days and we will always improve, as long as we have the opportunity we will look for it. When we have news we will bring it.”

United have so far signed Leny Yoro, Joshua Zirkzee, Noussair Mazraoui and Matthijs de Ligt in the summer window. “Yes, I am very pleased [with this],” he said. “They’re [recruits] showing we’re going in the right direction, we know as a club we have to catch up but it shows our ambition, the way we want to go. We have done good business, very good players, quality players who will add, contribute to our squad.”