Keown wrote in the Daily Mail: "Arsenal are on fire and while much of the praise is rightly going to the forward players, there has been great resilience at the back this season.
"Koscielny is like a heat-seeking missile. He sees where the danger is and homes in to clear it. There is no better one-on-one defender in the Premier League. He is confident, too, and looks like he knows there's not a player who can get past him. Technically he is sound: he looks like he could play in midfield.
"Mertesacker is more solid, but he is intelligent in his play and how he reads the game. He's in control of that back line, plays with a steady head and is great in the air. He looks slightly more of a leader than Koscielny but the two work well together.
"It's not dissimilar to when I played alongside Tony Adams. I could handle myself in the air, but it's good to have a player alongside you who can dominate that battle. Mertesacker does that for Arsenal, just as Adams did. People have compared Koscielny to me, though I'm not sure I was as mobile as he is! But I do think he has the potential to be better than I was."
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