Thomas Tuchel explains why Chelsea were "lucky" in FA Cup win over Sheffield United

The Blues won 2-0, courtesy of an Ollie Norwood own goal and Hakim Ziyech’s late strike, but that scoreline fails to tell the whole story as a much-improved second-half showing from United ran the home side close.

David McGoldrick somehow headed wide from a few yards out in the best chance of the game, while substitute Rhian Brewster saw a shot deflected wide late on.

And Tuchel admitted: “It was a tough match, we had a good first half and controlled everything but second half, we lost control.

“We were clearly tired, and there was alack of concentration against a strong opponent in the second half.

“So we were lucky to keep the clean sheet, we allowed too many chances but the target was to go through and we reached it.

“We let them come back because we had full control in the first half and had a big chance to finish the game early.

“We made too many easy mistakes and lost duels and concentration and momentum. These things can happen, I’m happy we had help from the bench and we take the win.”

United, heavily depleted through injuries, included two wing-backs in their central defensive trio but went behind when Norwood deflected Ben Chilwell’s shot past Aaron Ramsdale.

Ramsdale saved well from Christian Pulisic but United improved after the break, with Enda Stevens heading wide and Oli McBurnie forcing goalkeeper Kepa Arrizabalaga into a smart save to his left.