Defensively, he's edging towards Carra's peak level. He's already better than Carra when it comes to taking the ball from deep in our half into the opponents' midfield and distributing it. He doesn't do this that often, but I feel that this aspect of him is as underrated as Agger's is sometimes overrated.
Agger does a fine job bringing the ball deep into opponents' territory but quite often doesn't do well enough with the pass at the end of the run - he'd do all the difficult bits dodging and selling opponents the wrong way but then make a sloppy risky pass at the end of the run that concedes possession and ignites a counter-attack. I think Skrtel is better with the final pass at this point as he tends to play the higher percentage (safer) pass at the end of his run.
When it comes to dealing with aerial balls at either end of the pitch though, neither of our centre backs come close to Hyypia. Improving, yes. Close? Not even. Hyypia's ability in the air was superb. When he went in to attack an aerial ball, you just felt very confident he'd win it, and send it where he wanted it to go. That level of authority in the air is what Agger and Skrtel still don't possess. Hyypia might get troubled by Drogba when the ball's on the floor, but he'd not betray any nerves when it comes to high balls. Agger and Skrtel, on the other hand, still look a bit panicky or jittery in this area, and they still get sloppy defending set pieces.
What I like about Skrtel is that he's improving, cutting out those rash challenges at the back and growing into a useful option for our set pieces up front. I'd say that taken individually, Skrtel and Agger are very good centre backs now. For me, if they're to make the step up to the next level, each of them needs to work on improving his ability in the air and concentration in games.
