Riyad Mahrez, Robert Huth and Jamie Vardy - three of the main protagonists of last season's title triumph - stunned the Hammers with first-half goals.

The Foxes showed no signs of a European hangover following their epic win over Sevilla, and although they may have a quarter-final meeting with Atletico Madrid on their minds Shakespeare knows they still need to get their domestic affairs in order.

Fortunately they faced a West Ham side playing as though they just want their 'historic' first season at their new stadium to end as quickly as possible.

Manuel Lanzini briefly halved the deficit with a free-kick but they were booed off at half-time, and although Andre Ayew pulled another back after the break Leicester repelled a late rally to claim all three points.

Rejuvenated under Shakespeare following Claudio Ranieri's sacking last month, the first half was once again a throwback to last season's flying Foxes.

West Ham simply could not cope with the pace and before they knew it the hosts were 2-0 down.

In the fifth minute Mahrez swung in a cross towards Vardy and Shinji Okazaki, but both forwards missed it - as did West Ham's defence - as the ball flew into the corner of the net.

Two minutes later, from a Leicester free-kick, Marc Albrighton clipped the ball into the box with the outside of his boot and the unmarked Huth nodded in the second.

West Ham were dealt another blow after a quarter of an hour when captain Winston Reid went down clutching his leg and had to be replaced.

But they grabbed a lifeline in the 20th minute after Michail Antonio was fouled by Danny Drinkwater and Lanzini curled in a superb 20-yard free-kick.

Ayew and Michail Antonio fired wide and Andy Carroll had a goal ruled out, correctly, for offside as West Ham sensed they could haul themselves back into the game.

However, Vardy restored Leicester's two-goal lead before half-time when he pounced on the loose ball after West Ham failed to clear Albrighton's corner.

Vardy could have added a fourth after the break when he raced on to Mahrez's through-ball and lobbed Darren Randolph, only to clear the crossbar as well.

Instead West Ham pulled another back after Kasper Schmeichel got a hand to a Lanzini free-kick which was not on target, and instantly regretted it as from the corner Carroll's header was turned in by Ayew.

The suddenly re-energised Hammers poured forward but Schmeichel clawed out Carroll's header, Ayew skied a glorious chance and Cheikhou Kouyate's shot was blocked on the line.

And in stoppage time Schmeichel made a stunning point-blank save to deny Carroll as Leicester held out to take another big step away from relegation trouble, and continue to prove there is life in the champions yet.