And United were left to bemoan some familiar failings as they missed a gilt-edged chance in the first minute, when Oli Burke was sent clear but hit the side-netting rather than the target.
“It was a huge chance,” said Sky pundit Roy Keane at half time.
"McBurnie does well, a nice first touch and he’s got to hit the target. He looked like he didn’t have that belief and conviction. They’re not going to get many chances and they have to take them.”
They were punished when Mount finished off Timo Werner’s pass just a few minutes before half-time.
“The technique for the goal is not easy,” added Graeme Souness. “He knows he has to find the side-netting and he does.”
And Micah Richards wasn’t surprised to see it. He said: “Chelsea have been dominant, Sheffield United will still come out and give it a right good go but it’s that lack of quality that sees them in the position they’re in. They’ll have to come out all guns blazing in the second half.”