How to play for a draw In this video: Levon Aronian vs Magnus Carlsen Round 1 - 2013 Candidates Chess Tournament

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1.d4 Nf6 2.c4 e6 3.Nf3 Bb4+ 4.Bd2 Bxd2+ 5.Qxd2


And now, Kevin said: "You can tell that the game is going for a draw."

My question, how can you play a game knowing that you are going to draw? Do you have to defend? Exchange minor pieces? Mirror your opponent's move?

In theory, white always plays for a win, so how can black say: "I'm going to play this game and I'm going to draw". Carlsen seemed that he decided to go for a draw from the get-go, so what's the game plan for black in order to get a draw?
I imagine Kevin's comment was somewhat hyperbolic. My local database has 1464 games with the position after 5.Qxd2, of which only 47% were drawn (although I imagine that percentage goes up as the players' strength increases). That is still enough to give the variation a reputation as drawish, but not enough to reliably predict that the game will end in a draw.

There are certainly variations that are more drawish than others, for concrete reasons. The best current example is the Berlin variation of the Spanish, where Black gets the queens off the board early and White has had trouble making anything of his positional advantages in the ensuing endgame.

In general the way that a game becomes more likely to have a decisive result is due to imbalances between the virtues of the two sides. The obvious example is a gambit, where one player has better development and the other player has an active pawn. In a situation with few imbalances (for example, the Exchange French or Exchange Slav), it is more difficult to play for a win.