Answers.Body: <p>As I understand it, the purpose of <code>2... a6</code> is to keep a white piece (usually knight or bishop) off b5.</p>
  
  <p>It seems premature, because white might not want to go there anyway (for some time). Meaning that it could easily become a wasted move.</p>
  
  <p>As White, I would concentrate on king side development, knowing that b5 was "off limits," but not caring, because I have "better" things to do.</p>
  
  <p>One disadvantage of a6 is that Black may want to play a5 later to try to "chase" a White knight on b3. But if he does so, he would have wasted a move with a6. As White, I might try to "transpose" into that variation so that Black has wasted a move.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2012-05-01T19:07:59.220Z
Answers.LastActivityDate: 2014-11-09T15:12:38.387Z
Answers.LastEditDate: 2014-11-09T15:12:38.387Z
Answers.UserDisplayName: Tom Au
Answers.Body: <p>a6 serves three purpose .</p>
  
  <ol>
  <li>It is a waiting move in Sicilian as like Black waits for White's Plan . </li>
  <li>It is the start of Q-Side Counter Play from black . As in Sicilian Black generally plays on the Center &amp; Q-side .</li>
  <li>Generally in Sicilian the Black Queen's favourite Square is c7 . You may see this move in Kan/Taimanov/Najdorf etc . When Black Plays a6 then it covers the b5 Square which prevents White's Knight to come to b5 and attack the c7 Queen which costs a Tempo to Black .</li>
  </ol>
  
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Answers.CreationDate: 2017-02-23T14:22:26.090Z
Answers.LastActivityDate: 2017-02-23T14:22:26.090Z
Answers.UserDisplayName: Seth Projnabrata
Answers.Body: <p>This is called the O'Kelly variation of the Sicilian.</p>
  
  <p>If white plays normally (i.e. <code>3.d4 cxd4 4.Nxd4 Nf6 5.Nc3</code>), then black can eventually kick the d4 knight with <code>...e5</code> when the knight doesn't have any great squares.  In this case, <code>2... a6</code> keeps the knight from moving to the natural b5 square (as in the Sveshnikov Sicilian).  This will allow black to quickly play <code>...d5</code> with equality.</p>
  
  <p>White's best plan is to play either <code>c3</code> or <code>c4</code> trying to prove that black's move <code>2... a6</code> is not a good developing move.  When white plays <code>c3</code>, the natural plan is to follow up with <code>d4</code>, and then if black plays <code>...cxd4</code>, white will respond with <code>cxd4</code>, gaining a classical pawn center.  When white plays <code>c4</code> instead, white's plan is to set up a <a href="http://en.wikipedia.org/wiki/Mar%C3%B3czy_Bind">Maroczy bind</a>.</p>
  
  <p>An unambitious plan for white would be to play into a closed Sicilian - in the closed Sicilian, black frequently plays a6-b5 in order to get counterplay on the queenside.  Furthermore, in the closed Sicilian, tempi matter a lot less because the position will not change radically from one move to the next.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2012-05-01T18:51:50.697Z
Answers.LastActivityDate: 2012-06-09T20:31:16.707Z
Answers.LastEditDate: 2012-06-09T20:31:16.707Z
Answers.UserDisplayName: Andrew
Body: <p>Once I encountered an opponent who used a very early a6 in his Sicilian Opening. </p>
  
  <pre><code>[FEN ""]
  
  1. e4 c5 2. Nf3 a6
  </code></pre>
  
  <p>What could have been his objective with this move and how should I have have countered it?</p>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2012-05-07T06:08:56.450Z
Comments.Text: As a side-note: The moves 1.e4 a6 2.d4 b5 were played by Anthony Miles (as Black) beating the then-reigning world champion Anatoly Karpov with it in 1980(?!). These moves even got a name (Baker Defence) :)
Comments.UserDisplayName: Ray
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2014-11-10T11:52:43.447Z
Comments.Text: One possibility is 3.d4 cxd4 4.c3 transposing to the Smith-Morra gambit. I believe Fischer played this once.
Comments.UserDisplayName: bof
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-09-28T23:14:09.120Z
Comments.Text: On 3.d4 cd 4.Nxd4 Nf6 5.Nc3 e5! Black has good play. So you should choose 3.c3/3.c4.
Comments.UserDisplayName: Inertial Ignorance
Tags: <sicilian-defense><opening>
Title: What are the consequences of an early a6 in the Sicilian?
ThreadText: # What are the consequences of an early a6 in the Sicilian?
  
  (Asked by: username_0 on 2012-05-01)
  
  Once I encountered an opponent who used a very early a6 in his Sicilian Opening.
  
  ```
  [FEN ""]
  
  1. e4 c5 2. Nf3 a6
  
  ```
  
  What could have been his objective with this move and how should I have have countered it?
  
  **Tags:** sicilian-defense, opening
  
  > **Comments:**
  > **username_1**: As a side-note: The moves 1.e4 a6 2.d4 b5 were played by Anthony Miles (as Black) beating the then-reigning world champion Anatoly Karpov with it in 1980(?!). These moves even got a name (Baker Defence) :)  
  > **username_2**: One possibility is 3.d4 cxd4 4.c3 transposing to the Smith-Morra gambit. I believe Fischer played this once.  
  > **username_3**: On 3.d4 cd 4.Nxd4 Nf6 5.Nc3 e5! Black has good play. So you should choose 3.c3/3.c4.  
  
  ---
  
  ## 3 answers
  
  ### Answer by username_6 on 2012-05-01. Score: 38 | Accepted answer
  
  This is called the O'Kelly variation of the Sicilian.
  
  If white plays normally (i.e. `3.d4 cxd4 4.Nxd4 Nf6 5.Nc3`), then black can eventually kick the d4 knight with `...e5` when the knight doesn't have any great squares. In this case, `2... a6` keeps the knight from moving to the natural b5 square (as in the Sveshnikov Sicilian). This will allow black to quickly play `...d5` with equality.
  
  White's best plan is to play either `c3` or `c4` trying to prove that black's move `2... a6` is not a good developing move. When white plays `c3`, the natural plan is to follow up with `d4`, and then if black plays `...cxd4`, white will respond with `cxd4`, gaining a classical pawn center. When white plays `c4` instead, white's plan is to set up a [Maroczy bind](http://en.wikipedia.org/wiki/Mar%C3%B3czy_Bind).
  
  An unambitious plan for white would be to play into a closed Sicilian - in the closed Sicilian, black frequently plays a6-b5 in order to get counterplay on the queenside. Furthermore, in the closed Sicilian, tempi matter a lot less because the position will not change radically from one move to the next.
  
  
  ---
  
  ### Answer by username_4 on 2012-05-01. Score: 17
  
  As I understand it, the purpose of `2... a6` is to keep a white piece (usually knight or bishop) off b5.
  
  It seems premature, because white might not want to go there anyway (for some time). Meaning that it could easily become a wasted move.
  
  As White, I would concentrate on king side development, knowing that b5 was "off limits," but not caring, because I have "better" things to do.
  
  One disadvantage of a6 is that Black may want to play a5 later to try to "chase" a White knight on b3. But if he does so, he would have wasted a move with a6. As White, I might try to "transpose" into that variation so that Black has wasted a move.
  
  
  ---
  
  ### Answer by username_5 on 2017-02-23. Score: -1
  
  a6 serves three purpose .
  
  1. It is a waiting move in Sicilian as like Black waits for White's Plan .
  2. It is the start of Q-Side Counter Play from black . As in Sicilian Black generally plays on the Center & Q-side .
  3. Generally in Sicilian the Black Queen's favourite Square is c7 . You may see this move in Kan/Taimanov/Najdorf etc . When Black Plays a6 then it covers the b5 Square which prevents White's Knight to come to b5 and attack the c7 Queen which costs a Tempo to Black .
  
  
  ---
  
  