Thank god he's ok. I was worried about him when I first saw that start in live. But red card was too harsh as Llorente clearly touch the ball first.
As I understand the rules it doesn't save you even if you touch the ball first.
The red card is justified because some of the 5 criteria for a red card is fulfilled (according to international football law at least - I don't know if spanish football-law is very different). As I see it, 3 of them are fulfilled in this case:
(1) Primarily because of directions of feet - the tackle is made with the studs-up around/a little below the knee-area (that justifies red card at any time, but is rarely called all by itself)
(2) Combined with his use of excessive force (speed counts)
(3) Combined with his lack of control over the tackle (no feet on the ground - a standing tackle would lean more to yellow)
(4) Possibility of playing the ball: Possible as he actually plays it before collision.
(5) Willingness to play the ball: He clearly wants to and the hit is accidental.
Although 4)+5) isn't fulfilled you can still give a red card, when the others are fulfilled.
Maybe you remember the Luís-challenge against Messi - he also touches the ball first, but the red card is justified:
[youtube]_rhFMG9SXJM[/youtube]
The same criteria in that situation, and that is actually a slightly less clear red card:
(1) Primarily because of directions of feet - the tackle is made with the studs-up right on the knee (red card in itself)
(2) The speed with which he enters the tackle is not that bad in this situation.
(3) He has pretty good control over the tackle (standing with one leg)
(4) Possibility of playing the ball: Possible as he actually plays it just before collision.
(5) Willingness to play the ball: He wants to play the ball, but maybe continues longer than necessary to play to it.
This red card is also justified primarily because of 1).