Chelsea's defence will have to be on their toes when they are up against Manchester United's in-form attacking trio which is the most potent in the country in Sunday's FA Cup semifinal, manager Frank Lampard said on Friday.

United forwards Marcus Rashford and Anthony Martial have scored 22 goals each in all competitions this season while 18-year-old Mason Greenwood has also had a breakthrough season with 16 goals so far.

Lampard also said the mid-season addition of midfielder Bruno Fernandes has vastly improved United's attack as Ole Gunnar Solskjaer's side looks to extend its unbeaten run in all competitions to 20 games.

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“We know they are playing well, they've got a very potent front three, the most potent in the country on pure numbers,” Lampard told reporters in a virtual news conference.

“Fernandes has made a huge difference after coming in in January. You see the strength he's brought to the team and their individual qualities. We have to be confident and deal with these threats.”

Solskjaer had previously said that Chelsea had an unfair advantage having played last played on Tuesday, giving the London side more time to recover, while United played on Thursday but Lampard disagreed with that assessment.

Kante to miss the clash

“No, I don't think we do (have an unfair advantage),” Lampard said. “We have played Saturday, Tuesday. They played Monday, Thursday.

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“We both played two games this week, it's a busy period, you play and recover.”

Lampard confirmed N'Golo Kante would miss the clash at Wembley as the midfielder had still not recovered from a hamstring injury.

“The squad is okay but N'Golo Kante won't be fit for the match,” he said. “Other than that we have a few niggles.”