Queen's Gambit Accepted: Old Variation, Christensen Gambit

In the Queen's Gambit Accepted: Old Variation, Christensen Gambit, the move d4 is played to control the center and gain space. By pushing the pawn to d4, White restricts Black's pawn on d5 and prepares to develop the pieces. This move is a common opening in chess and can lead to various tactical and positional ideas. Playing d4 also opens up lines for the bishop and queen to be developed.

The move d5 is a popular response for Black after 1. d4. It immediately stakes a claim on the central square e4, aiming to control the center. Also, d5 allows Black's light-squared bishop to be developed to an active square. By advancing their d-pawn, Black aims to equalize the position by countering White's strong control of the center. Moreover, the move d5 opens up lines for Black's pieces and may lead to various attacking and tactical possibilities.

The move c4 is known as the Queen's Gambit and is a common response by White to Black's d5. The pawn on c4 aims to control the center and creates a pawn chain with the pawns on d4 and e3. By advancing the c-pawn, White also prepares to develop their pieces, such as the knight on c3 and the bishop on either d3 or e2. Moreover, c4 allows White to attack Black's pawn on d5 and threaten to capture it, thus giving White additional space in the center. In sum, c4 is an important move in many variations of the Queen's Gambit.

In the Queen's Gambit Accepted: Old Variation, Christensen Gambit, Black plays dxc4 in response to White's move c4. By capturing the pawn on c4 with the d-pawn, Black immediately challenges White's control of the center. Moreover, dxc4 opens up lines for Black's queen and bishop, potentially allowing for quick development. However, playing dxc4 also creates a weakness in Black's pawn structure on c6. On the other hand, Black aims to gain space and fight for central control by taking the pawn on c4. In sum, dxc4 is a common and important move in many variations of the Queen's Gambit Accepted.

The move e3 in response to Black's capture on c4 is a common and solid move in the Queen's Gambit Accepted. The pawn on e3 aims to support the controlled center and create a solid pawn structure. By advancing the e-pawn, White also prepares to develop their light-squared bishop to d3, which is a natural square for the bishop in many variations of the Queen's Gambit. Moreover, e3 protects the pawn on d4 and prevents any potential attacking ideas by Black's queen or bishop. In sum, e3 is a useful move to solidify White's control of the center and prepare for further development.

In response to White's e3, Black can play e5. The move e5 aims to immediately challenge White's control of the center and potentially open up lines for Black's pieces. By advancing the pawn, Black also prepares to develop their light-squared bishop to a more active square. Additionally, e5 may discourage White's bishop from developing to d3, as the pawn can potentially attack this square. However, playing e5 also weakens Black's pawn structure on d5, which is an important pawn for Black's control of the center. In sum, e5 is a dynamic move that aims to create counterplay against White's central pawn structure.

In the Queen's Gambit Accepted: Old Variation, Christensen Gambit, White can play Bxc4 in response to Black's move e5. The bishop takes control of the c4 square and develops actively. Moreover, Bxc4 puts pressure on Black's pawn on d5, making it difficult for Black to protect this pawn. In some variations, White can also aim to launch a quick attack on Black's king by setting up a battery with the queen on the long diagonal towards h7. However, Bxc4 does have some drawbacks, as it moves the bishop twice in the opening and gives the opponent time to develop their pieces. Additionally, Black may be able to exploit the pin on the c-file with a move like Qe7, thus putting pressure on White's bishop. In sum, Bxc4 is a natural and tactical move that can create some exciting play in the early stages of the game.

In response to White's move Bxc4, Black can play exd4. By capturing the pawn, Black opens up the center and also gains a tempo by attacking White's bishop. Additionally, exd4 can potentially weaken White's pawn structure if White recaptures with the e-pawn. Moreover, capturing on d4 allows Black's dark-squared bishop to be developed to an active square like f5 or g4. However, playing exd4 also creates an isolated pawn on d4 which can become a target later on in the game. In sum, exd4 is a natural move that aims to develop Black's pieces and challenge White's control of the center.

In response to Black's move exd4, White can play Qb3. The queen attacks Black's pawn on b7 and also puts pressure on the c6 pawn, potentially creating tactical opportunities in the center. Moreover, Qb3 develops the queen actively and prepares to castle queenside, which is a common plan in many variations of the Queen's Gambit. Additionally, Qb3 adds a threat to the position, as the queen may potentially attack Black's king in later stages of the game. However, Qb3 does put the queen in a slightly exposed position and may allow Black to develop their pieces more actively. In sum, Qb3 is an aggressive and active move that aims to create potential weaknesses in Black's position while preparing for White's next moves.

In the Queen's Gambit Accepted: Old Variation, Christensen Gambit, Black can play Qe7 in response to White's move Qb3. The queen defends the pawn on b7 and also blocks the long diagonal, preventing any potential attacks on h7. Additionally, Qe7 develops the queen actively and prepares to castle kingside. Moreover, Qe7 puts pressure on White's bishop on c4, as the queen and bishop are now on the same diagonal. However, playing Qe7 may delay Black's development of their kingside knight, which is an important piece in many variations of the Queen's Gambit. Additionally, Qe7 does not immediately create counterplay against White's central pawn structure. In sum, Qe7 is a solid move that aims to defend Black's position and prepare for further development.

In response to Black's move Qe7, White can play Nf3. The knight develops to a natural and central square and also prepares to castle kingside. Moreover, Nf3 puts pressure on Black's pawn on d4 and also attacks the weakened f7 square, potentially creating tactical opportunities in the center. Additionally, Nf3 allows White's light-squared bishop to be developed to a more active square like d3 or e2. However, playing Nf3 also blocks the development of White's kingside knight, which may be needed to defend the king later on in the game. Additionally, Nf3 does not immediately create any tactical threats against Black's position. In sum, Nf3 is a standard move that develops White's pieces and prepares for further positional and tactical ideas.