Calvert-Lewin added a third in stoppage time when he raced on to a through-ball from the excellent Idrissa Gueye.

Cardiff were as poor as Everton were competent and their failure to manage one on-target attempt will add to their growing relegation fears, especially as six of their final 10 games are away from home and the likes of Chelsea, Liverpool and the two Manchester clubs remain on their itinerary.

Both sides came into the contest low on confidence, with Cardiff only one point above the drop zone after Friday's 5-1 humbling at home to Watford.

Three successive defeats had left Silva feeling the heat from an increasingly sceptical Everton fan base, and the Portuguese was in desperate need of a victory ahead of Sunday's Merseyside derby with Liverpool.

The anxiety around the two sides was perhaps reflected by both managers making five changes, and Everton appeared to be unsettled by their defensive reshuffle inside 90 seconds when Phil Jagielka under-hit his back pass to goalkeeper Jordan Pickford.

Kenneth Zohore raced on to the loose ball, but his square pass across goal lacked conviction and Lucas Digne prevented Nathaniel Mendez-Laing from turning it into an empty net.

Theo Walcott flashed a couple of volleys wide as Everton dominated possession and Cardiff pair Sean Morrison and Leandro Bacuna collected cautions for mistimed tackles.

But Everton's final pass often went astray as Cardiff failed to trouble Pickford, who was being watched by England assistant manager Steve Holland.

Zohore rushed one angled attempt after Aron Gunnarsson found him unmarked, before a rare moment of quality saw Everton strike four minutes before the break.

Cardiff defender Joe Bennett was culpable on two occasions within a matter of seconds, his wayward pass gifting Everton a throw-in before the full-back allowed Seamus Coleman to run in behind him and burst on to Morgan Schneiderlin's pass.

Coleman was close to being offside, but he delivered an intelligent cross which Sigurdsson swept home with aplomb.

Cardiff showed more urgency after the break, with Digne booked for a foul on Zohore and the Dane sprinting clear of Michael Keane down the left-hand channel.

Zohore's cross into the six-yard box signalled danger for Everton, but Schneiderlin was back to clear.

It was to prove a decisive moment as Everton substitute Bernard proved too elusive for Bruno Ecuele Manga and Neil Etheridge could only paw his cross into Sigurdsson's path.

Sigurdsson took aim with his trusty left foot, dispatching his 11th league goal high into the Cardiff net, and he had taken his leave before Calvert-Lewis applied the final gloss.

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