Tkachenko, Erik vs. Vaibhav Kalpaka - U.S. Open Championship and State Tournaments of Champions 2024 1-0

In the U.S. Open Championship and State Tournaments of Champions held on July 30, 2024, in the game between Erik Tkachenko and Vaibhav Kalpaka, Black played the move e5. This move inadvertently led to a loss of material due to the piece being left without defenders. It missed the opportunity to counterattack or protect an underdefended piece effectively. Additionally, it neglected a superior chance to mount a more substantial threat, and the piece was sacrificed unnecessarily. The move also missed the chance to reveal an attack on an opposing piece and did not capitalize on potential defensive improvements. Instead of blocking White's attack or defending an unprotected piece, it allowed White to gain a positional advantage. Overall, e5 was a critical error in the game, sacrificing piece safety and missing various opportunities for better defensive and offensive play.