Nah, Grosso is weak and a liability defensively, man on man, he is quite lost. Kolarov has allways had the physically and toughness to deal with players (Grosso doesnt), but what he has improved from being defensively weak, is his awareness and positioning, and being tactically sound, instead of just be gunho as he used to be. Seen him mark out and hold down his flank defensively quite well, and not just bomb forward offensively like a headless chicken as earlier.