After Newcastle lost possession in a dangerous area, skipper Jamaal Lascelles was punished for a foul on Leicester’s James Maddison.
Tielemans stepped up and lashed the ball home to give The Foxes a half-time lead.
The decision infuriated Magpies fans, some of whom felt Maddison had dived while others directed their frustration towards the captain.
Newcastle legend Alan Shearer sparked debate as he tweeted: “Dive?"
He then added: “Any danger VAR? #dive”
Here’s how supporters reacted…
@Saandaaah: “Biggest League in the world has the Worst refs in Europe. City’s pen yesterday and now, this clear dive, everyone else can see it, how can’t they?”
@NUFCRosie: “Maddison is half way in the air by the time he reaches Lascelles.”
@clementmnene: “I still can't tell how VAR failed to overturn that penalty decision.”
@FelixLongbrook: “Shelvey lazily giving the ball away was the catalyst.”
@Ben98whiteley: “Time to get Lascelles out for Fede. Continues to prove how much of a liability he is.”
@TheMokPope: “Was a dive but a stupid challenge. How many penalties has Lascelles given away?”
@Jasonwearmouth: “Pen number 3 given away by Lascelles this season. Fernandez is a must!!!”
@singram999: “He hung a leg out that let him dive over it.”
@joe68mac: “Captain clumsy gives away another penalty. 3 this season, why is Fernández not in the starting line up instead?”
@madebyclancy: “Don't know how people are blaming Lascelles for this.”
@Rickardo_nufc: “Very poor but huge dive that. Played for it.”
@Common91: “I turned over from the F1 to watch Newcastle, missed Max [Verstappen] win the title, saw NUFC concede a penalty.”