Having been humbled at home to Brighton on Sunday, Steve Bruce’s men emphatically booked a fourth-round trip to Newport as his much-changed side ran amok at the empty Mazuma Stadium.
Joelinton netted twice as Newcastle hit five in an opening period made all the more difficult for Morecambe by Toumani Diagouraga’s red card, with the hosts digging deep to restrict the Premier League side to just two more after the break.
There were plenty of big names on display despite Bruce’s nine changes in Lancashire, where £40million signing Joelinton gave the visitors an early lead.
Miguel Almiron rounded the goalkeeper to add another, before Jacob Murphy curled home and the Magpies’ Brazilian frontman scored a screamer from distance.
The League Two side saw Diagouraga sent off for a lunge on Sean Longstaff before Isaac Hayden smashed home in stoppage time as Newcastle scored five first-half goals in a match for the first time since 1993.
The second period was one of damage limitation for Derek Adams’ Shrimps, who only conceded Jamaal Lascelles’ header and a Sam Lavelle own goal despite the continuing one-way traffic.
Newcastle were relentless from the outset on Wednesday, with Joelinton sweeping home an Almiron pass just five minutes in.
The goalscorer was caught napping when Murphy’s cross hit a post soon after, but the Magpies continued undeterred and extended their lead in the 20th minute.
Almiron all too easily got behind the Morecambe backline and coolly rounded Shrimps goalkeeper Mark Halstead before lashing home.
Mark Gillespie, making just his second appearance for Newcastle, prevented Diagouraga pulling one back for the home side at the other end, with any hopes of a comeback proving shortlived.
Impressive Murphy easily won a 50-50 challenge with Stephen Hendrie and made a beeline towards the Morecambe goal, curling a left-footed shot in from 20 yards in the 27th minute.
Morecambe’s evening quickly went downhill from there, with Joelinton driving in from the left touchline and unleashing a stunning 25-yard strike that left Halstead with no chance.
As if a four-goal deficit was not enough, Diagouraga was shown a straight red card for a poor challenge on Longstaff in the 33rd minute.
The Newcastle midfielder was able to continue after treatment and tried his luck from distance, just as Hayden did in first-half stoppage time with an effort that whizzed home.
Newcastle continued in the same vein after the break, with skipper Lascelles heading home a Matt Ritchie corner at the near post in the 51st minute.
Hayden was denied a second by Halstead and Almiron flashed over, while John O’Sullivan’s goal-line clearance prevented Emil Krafth from adding a seventh.
Substitutes Andy Carroll and Ryan Fraser went close before Lavelle inadvertently turned a Ritchie flick into his own goal at the death.