I'd say Riquelme and Valderrama are the best players I've seen in terms of shielding the ball at walking pace
I agree, Zidane was a bit faster than these 2 players but I can tell you that he was strong too, you can particularly see that at the end of his carreer when had less pace/agility (although he had never been really agile) but his ball protection was tremendous.
Pirlo does also the same thing, shielding the ball at walking pace, but he is not a strong player in terms of BB.
I agree, I think when I mentioned "shield" the real meaning of the context in which I mentioned the word got lost in translation. Yes, Zidane was very strong (and he was also very big as well and not nearly as slow as people seem to remember these days) and was as good as it gets in terms of ball protection, in my opinion. However, what I meant by "shield", is when you got a player like Riquelme for example, not running with the ball, and instead standing there shielding the ball at walking pace, and coming out victorious.
I have seen a lot of matches of Zidane, and *from what I've seen* Zidane had a very consistent tendency of loosing the ball when he tried to protect the ball like Riquelme would. Zidane, in my opinion, was more like Andres Iniesta (but obviously much stronger than Iniesta), a virtuoso player with excellent ball protection skills, but a player who is likely to loose the ball if he tries to do what Riquelme used to do.
Pirlo is the player (from the current generation) who I find is the most similar to Valderrama, but obviously Pirlo can score from free kicks, can score long range goals, and has proven himself at the highest level for well over seven years now. Having said that though, I've never seen Pirlo do some of the things that Valderrama could do.