From what I've watched, he's great on the ball, fast and deceptively strong. Straight from Lezama.
But he's only played a few games of professional football so it remains to see how good he actually is, but he's made a great CB duo with Laporte. One of the new sensations of the season so far at least.
Should keep an eye on him, Yerry Mina whom we have a 9m option on, and last but not the least, Davinson Sanchez who we wanted to sign, but couldn't because he wanted to play regularly at the top level. He signed for Ajax and has been a rock for them so far.
After 2018, I can see Mascherano leaving. He'll be 34 and has said he want to end his career in Argentina for River. Mathieu will also be gone by then. Pique, Umtiti, Marlon and someone else would have to step up or be signed and since there doesn't seem to be much interest in our academy CBs, I guess that player has to come from somewhere else.