Right, lets nail this 'Tav can't defend' thing.
First of all, much of this is based on him being caught out of position. As a modern attacking full back that will happen a fair bit. It's the job of the midfield to drop in and cover when he's in attack.
Secondly, let's compare him to the billion dollar wonderkid from the Eastend.
For anyone not familiar with them the closer each point is to the edge the closer that player is to being the best in the league with that stat.
Note the size of Tav's compared to Tierney's. It shows that he's excelling in all areas of his game, both attacking and defending.
We'll look at defending only though as this is where the criticism seems to be.
Tierney is the best in the league at winning defensive duels, winning 27% compared to Tav's 21.5%. It's important to note though that Tav is facing 9 per game compared to Tierney's 5.5. So Tav is involved in more defensive battles, probably due to our midfield being over run at times.
Outwith that Tav has more interceptions per game, 6 to Tierney's 4.5 and
importantly Tav blocks more than double the crosses Tierney does, over 42% compared to Tierney's 20%. This is something we constantly see him getting criticised for and yet he's doing very well in that area.
Let's not forget as well that Tav has been playing alongside an ever changing central defence that has been a bombscare at times and a midfield that has been over-run due to bad organisation.
And that is the case for the defence M'lud