After constructing A Magnus Carlsen Game Collection, my first task was to get a feel for the opening systems used by the Norwegian GM. I started by taking his games as White. I noted the frequency of his first moves, then noted the responses by his opponents to those moves. I repeated this for the second move, the third move, and so on, until I reached a point where there were only a handful of moves in the current variation. You might think of this as creating a tree of opening variations based on his repertoire. Then I did the same for his games as Black.
What did I learn from this exercise? Not much, really. Carlsen plays everything. If a move is sound he plays it. If, in whatever position, there are several sound continuations, he plays them all. He must be an extremely challenging opponent to prepare for, because he's likely to play anything.
I even found a few games where Carlsen played moves that are considered less than sound. For example, here are three games where he opened 1.a3 (Anderssen's Opening) as White.
- Magnus Carlsen vs Vassily Ivanchuk; Amber Tournament (Blindfold) 2010
- Magnus Carlsen vs Pavel Eljanov; World Blitz Championship 2010
- Magnus Carlsen vs Alexander Grischuk; World Blitz Championship 2010
The links are to the corresponding games on Chessgames.com, usually with commentary. Here's a game from a few months ago where he played 1.a4.
One of the Chessgames kibitzers to that game quoted Chessvibes:-
Carlsen starting his game against Radjabov with 1.a4 had a little history. During the previous World Blitz Championship, in Moscow, November 2010, Radjabov had said to Carlsen: "Everyone is getting tired. You might as well start with 1.a4 and you can still beat them."
Carlsen won that game with 1.a4. Maybe Radjabov should have suggested 1.g4. What are the rest of us mere mortals supposed to make of this?