Leicester started strong with Newcastle number one Martin Dubravka making two early saves to keep the score 0-0. It was Loanee Joe Willock who increased his profile run of goalscoring form after poaching the ball from Çağlar Söyüncü and cooly finishing it past Kasper Schmeichel to kick things off in the Magpies' rout.
Willock overtook Newcastle United legend Andy Cole to become the youngest player to score in four consecutive Premier League games. The loanee also is the first player in a Newcastle shirt to score in four consecutive matches since Papiss Cisse.
Newcastle made it 2-0 with a thunderous header from Paul Dummett. Callum Wilson added a second-half brace to put Newcastle 4-0 in front.
Leicester City added two consolation goals through Marc Albrighton and Kelechi Iheanacho.
Story of the game
A slow start to the game with neither side with control of possession favouring the home side. Newcastle won a pair of freekicks with the pace of Allan Saint-Maximin and Miguel Almiron stretching Leicester. The subsequent delivery from Jonjo Shelvey was headed just wide by Federico Fernandez.
Newcastle again knocked at the door when Wilson broke away from Leicester defenders with Saint-Maximin unmarked in the penalty area. The Frenchman's point-blank effort was saved brilliantly by Kasper Schmeichel.
The pressure that Newcastle enforced on Leicester was rewarded on the 20-minute mark as Joe Willock pounced on Çağlar Söyüncü and broke into the box finishing low to put The Magpies deservedly ahead.
Less than five minutes later, Leicester looked certain to equalise as Wesley Fofana rises highest from a Youri Tielemans free-kick, but Martin Dubravka equals his bullet header.
Newcastle still keeping a foot in the game with corners and half chances. Another Newcastle corner comes into the area, and Paul Dummett thundered home Newcastles second on 34 minutes. The Welshman's first goal in five years.
This awoke Leicester, and it was to be expected as the Foxes have recovered 20 points from losing positions this season as a well-worked move down the left-hand side left the inform Kelechi Iheanacho free at the back post. His effort is tame, and Dubravka gathered.
Leicester had another bite of the cherry on the stroke of half time as Jamie Vardy sneaked through the Newcastle backline and tried an ambitious chip on the oncoming Dubravka, again the Slovakian international pulled off a top-class save.
Leicester came out into the second half knocking on the door. Half chances, although they were for the first ten minutes of the second half, the Foxes showed flashes of why they are third in the Premier League.
Newcastle were perfectly happy to sit back and take the pressure with the pace to go forward and counter-attack; on the 63rd minute, that is exactly what The Magpies did as Matt Ritchie hit a long searching ball for Callum Wilson. Timothy Castange did not deal with it correctly as his sliding back pass fell short, and Wilson took it round the oncoming Schmeichel to make it 3-0 to the Magpies.
Callum Wilson grabbed his second nine minutes later with a superb team goal by Newcastle. The England international secured his 12th goal of the season with a second bite of the cherry, finishing from an acute angle.
Newcastle were entirely in control and until 79 minutes as Marc Albrighton thunderbolted the ball into the top corner from 16 yards out for a consolation goal.
Newcastle gets caught resting on their laurels in the 84th minute as Iheanacho drills a low effort past two Newcastle blockers into the bottom corner. Iheanacho has now secured 11 goals in 12 games.
Leicester smelt blood in the water as Newcastle leaked two goals in five minutes and piled the pressure on more and more.
Ex-Newcastle-man Ayoze Perez has a chance to make it 4-3, but Martin Dubravka stops the shots from two yards out. The fourth top-class save from the Newcastle number one.
It finished 4-2 to Newcastle, who thoroughly deserved all three points. Leicester will have themselves to blame for two of the goals conceded, but Newcastle are all but safe with the win.
Martin Dubravka, underappreciated
The Newcastle number one was on fine form again tonight, saving three close-range efforts. Despite being an attack-minded performance where the strikers will get all the plaudits. The Magpies shot-stopper deserves credit for keeping Newcastle in the game early. A good goalkeeper is hard to find. Once you have one, hold onto him. Newcastle have done that over the years, and Dubravka has earned the North-East side more points than he has lost.
History repeats itself in the strangest ways
Despite the two late goals, Leicester City finds themselves dropping more points with the chase for the Champions League places hotting up. The questions being asked are how is this happening to Leicester. Well, you only have to look back 12 months and see it happened before. This time feels different, however. Leicester needed the result against Newcastle to go their way as the final fixtures for the Foxes is a challenging run with Manchester United, Chelsea, and Tottenham Hotspur. The Foxes have not been good under pressure this season, and time will only tell if deja vu appears in Brendan Rodgers's mind.
Leicester City: Schmeichel; Ricardo Pereira, Söyüncü, Fofana, Castagne, Albrighton; Tielemans, Ndidi, Maddison; Vardy, Iheanacho.
Newcastle United: Dubravka; Murphy, Krafth, Fernández, Dummett, Ritchie, Willock, Shelvey, Almirón; Saint-Maximin, Wilson.