Eddie Howe's side welcomed Cambridge to St James' Park on Saturday afternoon and started a number of first-teamers.
Making his debut was Kieran Trippier, who became the club's first signing of the new Saudi-led regime on Friday afternoon.
It was Cambridge who made the headlines however thanks to Joe Ironside's strike in the 56th minute.
Jack Lankester thought he'd doubled his side's lead, but it was ruled out for offside much to the U's dismay.
Newcastle had Allan Saint-Maximin and Ryan Fraser in attack and first-choice goalkeeper Martin Dubravka between the sticks.
Joelinton nearly equalised right at the death with a header from Trippier's cross, but Dimitar Mitov managed to save.
Fans have reacted to the result and they think it's one of the biggest cup upsets in recent memory.
Beating Cambridge is not for everyone 🙃 pic.twitter.com/62o2AhfC3P— Marc - Fut Trader💙 (@MarcFUTTrader) January 8, 2022
Hey can you pass on a message? Just let our players know the whole world is laughing at them.— JAKE BUCKLEY 🇦🇺 (@TheMasterBucks) January 8, 2022
Embarrassing advertisement for the players we want to sign, we're playing like a relegation team. It's a disgrace.— Zlatan's burner🇳🇬 (@manlikefola_) January 8, 2022
Good job Kieran Trippier likes challenges as he’s went from winning La Liga and playing Real Madrid and Barca to losing at home to Cambridge from league 1 university team— Calum McGhee (@McgheeCalum) January 8, 2022
Newcastle's wretched run in cup competitions continues and it's the sixth time in 10 years they've been knocked out in the third round.
The Magpies will now need to turn their attention to Premier League survival, with the club currently sitting in 19th and two points from safety.
It's expected that the club will make more moves in the January window and among those linked are Lille defender Sven Botman.
The 21-year-old has impressed in France and helped Lille clinch the title over Paris Saint-Germain last summer.
Newcastle have the joint worst defence in the top-flight this season and hope the Dutchman can offer some quality at the back.
They've also been linked with moves for Pierre-Emerick Aubameyang and Anthony Martial, who are unhappy at Arsenal and Manchester United respectively.
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Featured Image Credit: Alamy
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