Dalot was only shown a yellow card after catching Doku's knee with a high boot, with the Portugal international only being handed a yellow card instead.
The tackle sparked conversation online, and fans agreed that such a challenge should have caused Dalot to be immediately sent off.
However, the video assistant referee (VAR), Craig Pawson, said the contact was "glancing and not with excessive force" as he backed up the yellow card decision.
Shearer spoke to BBC Sport about the challenge and suggested there could be something seriously wrong with the officiating in the Premier League:
"I think VAR got that terribly wrong. For me, that was a clear red card.
"Forget about whether the contact was 'glancing' or not. I can understand why the referee hasn't given it, it might have been difficult for him to see it, but when the VAR has two professionals looking at that it should have been a very easy decision to give a red card."
Sky Sports pundits Roy Keane, Daniel Sturridge and Micah Richards all felt the decision was wrong, in a rare moment where all pundits agreed that the referee was in the wrong.
Former United skipper Roy Keane said: “I’ve been down this road before, and I’ve given out some heavy tackles, (and) I’ve been on the receiving end of a few.
“To me, I’m no expert on red cards, but I think it’s a red.”