The Magpies faithful feel the 26-year-old may never be able to contribute enough at St James' Park.
For once, Newcastle United fans were actually calling for Florian Thauvin on Saturday afternoon.
Newcastle drew 0-0 with Stoke but some fans think bringing someone other than De Jong on would have given the Magpies a better chance of sealing all three points against the Potters.
And there are fears the 26-year-old may never be able to make an impact in the Premier League. De Jong has been extremely unlucky with fitness and injuries but, after over a season on Tyneside, the Dutchman needs to deliver some time.
There were even comparisons with his brother Luuk, who infamously failed during a loan spell at Newcastle.
Supporters slammed Siem's performance against Stoke and are wondering whether he will ever be suited to the Premier League and English football in general. After being introduced in the second half, the 26-year-old looked as though he had been on for the whole 90.
Here's how Newcastle fans reacted on Twitter to his display after coming on:
I said it during the week , De Jong is not good enough and never will be for the premier league.. #nufc— simon nicols (@sinicols) October 31, 2015
What do people think about De Jong ? we know he has class but is he suited to this league ? #nufc— Skirgey (@Skirgey) October 31, 2015
De Jong has to be cashed in on in Jan! Offers nothing! Zilch! Diddly squat! #nufc— Paul Shenton (@Paul_Shenton19) October 31, 2015
I know he's been injured and he's only coming on late but I swear I could do more than Siem De Jong. #NUFC— Cola (@Percycola) October 31, 2015
De Jong came on for the last 20 mins. He looked like he had just played for 365 minutes. #Nufc— Deka Petrie (@DekaD7) October 31, 2015
#NUFC Siem De Jong wins the best Halloween outfit award for being the most convincing Invisible man. Too slow man.— Amir Hussain (@_AmirHussain) October 31, 2015
The De Jong substitution had the reverse effect. Made us blunt especially on the counter. #NUFC— Toon Army India (@ToonArmyIndia) October 31, 2015