Thomas Tuchel has stated that he had to changed the team’s formation to back four for tactical reason.

Chelsea narrowly sealed their spot in the FA Cup quarter-final with a 1-0 win over Championship side Barnsley on Thursday night at Oakwell.

The German gaffer’s side progressed into the last eight despite a sub-par performance in Yorkshire as Abraham saved the day and spared a cup upset.

Tuchel said: “We changed to a back four and took Marcos [Alonso] out for this tactical change. Andreas [Christensen] had to go out because he had a headache. The changes made it a little easier to get into the opponent’s half and overcome the first press.

“We did it well at the start of the second half and played constantly in the opponent’s half.

“We scored the goal and I had the feeling that they increased the risk but we stepped down in the little decisions. Not enough courage and it was too deep for a long, long time.

“We clearly can play better, so yes I expected more but not in terms that I am frustrated.

“If you lack a rhythm and a bit of self-confidence and you have to show on this pitch, against an opponent that takes all the risk and plays the game of his life, that is not easy. We can do better but I don’t want to be too hard on the players.”

On playing Sheffield United in the last eight: “It’s going to be a tough one. They are a very physical team that presses high. They are organised but I am happy to have a home game. This is what we wanted.”