Crystal Palace manager Patrick Vieira knows it will be difficult to replace Conor Gallagher for Sunday’s FA Cup semi-final with Chelsea but has praised the “special” loanee for preparing this week like he is playing in the tie.

The terms of the midfielder’s loan agreement from Stamford Bridge meant he was unable to feature against the Blues this season and a written request for him to line up at Wembley was rejected by Thomas Tuchel’s side last week.

Gallagher’s energy and pressing role, in addition to scoring eight goals, has been a key feature of Palace’s transformation from a pragmatic counter-attacking side to one who aim to dominate possession after regaining the ball.

It has contributed towards one of the most exciting campaigns at Selhurst Park in years, with the Eagles fighting for a top-10 finish and at Wembley for the first time since 2016, when Manchester United beat them in the FA Cup final.

Cup success for Palace would be some cherry on top of what has already been an impressive debut season in the dugout for Vieira, but he will have to make this penultimate step without a key man.

“He is professional enough to understand the situation and deal with it, but of course there is the expression on the face and that doesn’t lie,” the Eagles boss said of Gallagher.

“It is difficult to find in the squad a player with Conor’s type of energy. We have different profiles and players who can score goals and create chances maybe more than Conor can do.

“Of course his profile is different, but we have players who are capable of bringing something different to the team.”

Gallagher will be at Wembley and will stay with the Palace squad at a hotel on Saturday, with his professionalism praised despite a difficult week.

Chelsea boss Thomas Tuchel revealed on Friday he personally apologised to the 22-year-old for denying him the chance to play in the semi-final.

Vieira added: “Conor has been like he is starting the game. He has been working well, working hard.

“We gave him a couple of days (off) in the week, but he is preparing himself like he is going to play and that is what makes him really special.”

Even though Chelsea have stopped Gallagher having the chance to haunt them, one man they no longer have a hold over is Marc Guehi, who completed a summer switch from across the capital to Palace last summer.

After an excellent loan in the Sky Bet Championship with Swansea, the Cobham academy graduate has kicked on even more after joining the Eagles on a permanent basis and regularly worn the captain’s armband.

Given his friendship with Gallagher, with the pair playing together for Chelsea, Swansea, Palace and most recently England, Guehi is sorry to see the all-action midfielder miss this clash.

He said: “Conor’s an important player. He has been vital for us this season, but we have a lot of good players in the side who can come in. We have seen that throughout the season, substitutes the manager has made coming in and really making an impact.

“Conor’s a big miss. but we have got a lot of good players in the team as well.”

If Palace stun Chelsea, it would mean Gallagher could get his FA Cup moment at Wembley for the final next month.

Guehi’s motivation is clear, he said: “Conor has been immense for us this season and the team doing well would allow him to play in that final because of what he has done this season, so hopefully we can get there.”