Not a fan of Rojo, but for all his flaws he does play with some presence and personality, which after watching Lindelof for a couple of months stands out massively. You have to be careful not to confuse that with competence though. Rojo is reckless, in all the ways he plays. Constantly thumping the ball long, diving into tackles, getting drawn out of position. In one v one battles he can be quite impressive but that is only one part of defending.
At this point in his Utd career, this is his 5th year, has he even had 50 decent games for the club?