A dramatic way to avoid ...Ba3.
1. e2e4  1... c7c6  2. d2d4  2... d7d5  3. b1c3  3... d5e4  4. c3e4 This was once the undisputed main line of the Caro-Kann Defense. Nowadays the advance variation (4.e5) is also very popular. 4... g8f6 The fashionable move, supplanting 4...Bf5 and 4...Nd7. 5. e4f6  5... e7f6 [%c_effect f6;square;f6;type;GreatFind;persistent;true] There was a time when capturing with the g-pawn was considered the best move, but today's computers have a clear preference for taking with the e-pawn. Despite having doubled pawns and granting White a dangerous pawn majority on the queenside, it seems that Black's free piece development is a good compensation. 6. c2c3  6... f8d6  7. f1d3  7... e8g8  8. d1c2  8... f8e8  9. g1e2 The critical position of this opening system. 9... h7h5 [%c_effect h5;square;h5;type;GreatFind;persistent;true] A somewhat surprising move, as it seems dangerous to advance the pawn two squares when White can still castle on the queenside. But practice has shown that White's attack doesn't arrive so quickly. 10. c1e3 White decides to go for queenside castling. There are over a thousand games in this position. 10... b8d7  11. e1c1  11... b7b5 [%c_effect b5;square;b5;type;GreatFind;persistent;true] Black advances on the queenside and prepares Nb6. 12. d4d5 [%c_effect d5;square;d5;type;GreatFind;persistent;true] The critical test. A similar position was played in the recently finished Women's World Cup, but in the game Muzychuk-Salimova, white's knight was on f3. As the machine points out, this small difference is helpful for White. 12... c6c5 [%c_effect c5;square;c5;type;GreatFind;persistent;true] A strong pawn sacrifice, well known by opening theory. We're following (among others) the famous game Duda-Carlsen, which ended a long undefeated streak by the world's number one. 13. d3b5  13... a8b8  14. b5a4 [%c_effect a4;square;a4;type;Mistake;persistent;true] This move immediately lands White in trouble. 14... e8e5 [%c_effect e5;square;e5;type;GreatFind;persistent;true] If you were wondering why the computer thinks this position is better for White with the knight on f3, this is one of the reasons: the e5-square cannot be used so easily. But with the knight on e2, Black has this move, with the plan of Nb6 followed by Bf5. 15. e2f4 A new move. White is already losing. 15... d7b6  16. a4b5 The bishop must cover the c4-square. 16... c5c4  17. b5c6  17... c8f5  18. c2d2  18... b6c8 A good move, paving the way for the queen. There are good alternatives as well. 19. g2g4 White desperately tries to distract Black from attacking the queenside. 19... h5g4  20. a2a4  20... a7a6 Taking the b5-square from the bishop and preparing ...Ba3. There are many winning moves.