user2873: [StartPly "8"]
[FEN ""]

1.d4 d5 2.c4 dxc4 3.e3 b5 4.a4 Ba6

White to move.
How to capitalize on this variation of Queen's Gambit Accepted for white? I've never seen this counter before.
Couldn't get pawn back and couldn't develop properly due to cramped queen-side.

user3944: Following from the last line:
[StartPly "8"]
[FEN ""]

1.d4 d5 2.c4 dxc4 3.e3 b5 4.a4 Ba6 5.axb5 Bxb5 6.Nc3 {If black tries to defend the pawn:} Ba6 7.Qf3 c6 {The only reply that doesn't instantly lose the rook.} 8.Rxa6 Nxa6 9.Qxc6+ Qd7 10.Qxa8+ Qd8 11.Qc6+ Qd7 12.Qxa6

Killing him.

user1485: You can play 5. axb5 and transpose to the answers to this question (Queen's Gambit Accepted with black trying to defend the c file pawn with 4... Bd7).

2873: <pre><code>[StartPly "8"]
[FEN ""]

1.d4 d5 2.c4 dxc4 3.e3 b5 4.a4 Ba6
</code></pre>

<p>White to move.</p>

<p>How to capitalize on this variation of Queen's Gambit Accepted for white? I've never seen this counter before.</p>

<p>Couldn't get pawn back and couldn't develop properly due to cramped queen-side.</p>
 3944: <p>Following from the last line:</p>

<pre><code>[StartPly "8"]
[FEN ""]

1.d4 d5 2.c4 dxc4 3.e3 b5 4.a4 Ba6 5.axb5 Bxb5 6.Nc3 {If black tries to defend the pawn:} Ba6 7.Qf3 c6 {The only reply that doesn't instantly lose the rook.} 8.Rxa6 Nxa6 9.Qxc6+ Qd7 10.Qxa8+ Qd8 11.Qc6+ Qd7 12.Qxa6
</code></pre>

<p>Killing him.</p>
 1485: <p>You can play <code>5. axb5</code> and transpose to the answers to <a href="https://chess.stackexchange.com/questions/4555/queens-gambit-accepted-with-black-trying-to-defend-the-c-file-pawn-with-4">this question</a> (Queen's Gambit Accepted with black trying to defend the <code>c</code> file pawn with <code>4... Bd7</code>).</p>
