David de Gea had a day to forget as Olivier Giroud and Mason Mount helped Chelsea outlcass Manchester United 3-1 in Sunday’s FA Cup semi-final at Wembley.

Giroud ensured Chelsea deservedly led with the help of slack goalkeeping from De Gea at the end of a half in which United lost Eric Bailly to a serious-looking heading injury.

De Gea was at fault again almost immediately after the restart when Mount doubled Chelsea’s lead with a shot a keeper of any level would hope to save.

The Spaniard was not entirely convincing when Harry Maguire put into his own net to compound a miserable day either, but – despite a late penalty from Bruno Fernandes – Frank Lampard’s side were good value for the win and can now look forward to a return to Wembley to face Arsenal in a rematch of the 2016-17 final.

Chelsea’s pressure had United on the back foot early on but Reece James’ stinging drive was the only save De Gea had to make, with Marcos Alonso wastefully putting a free header over.

United’s performance was at odds with their recent form and they saw Bailly taken away on a stretcher in a neck brace after a nasty clash of heads with Maguire.

After a lengthy delay, Giroud’s deft touch from Cesar Azpilicueta’s right-wing cross squirmed past De Gea, who might feel he should have done better, in the 11th minute of first-half stoppage time.

Just a minute after the restart De Gea’s outing got even worse when he allowed Mount’s seemingly unthreatening 20-yard effort under his body, albeit Brandon Williams’ wayward pass did his side no favours.

Marcus Rashford flashed a tantalising ball across the face of goal and Maguire headed wide when Willy Caballero flapped at a corner as United tried to muster a response.

But it was game over when Maguire got the final touch on Alonso’s drilled cross and De Gea was again beaten, with Fernandes’ clinical spot-kick after Callum Hudson-Odoi’s clumsy challenge on Anthony Martial providing scant consolation.