In the following ICC chess game, Megeser from Costa Rica playing White resigned on move 15 after allowing an unbreakable pin. White played 2. Qe2 against Black’s French defense. White’s slow play allowed Black to move his e pawn twice which liberated the well-known French Achilles heel , the c8 bishop. BTW, for you Frenchophiles who have read John Watson’s BOOK, he has repeated in both books that 2. … c5 is a great answer to 2. Qe2 since Queen is misplaced in a potentially open Sicilian defense.
After Be6 Nfd2, b5 wins a piece which is also Black’s reaction after Qa4. How did Megeser lose so quickly with the White pieces? He played Qb5 threatening the b7 pawn which was easily defended. White then played Nc4 which blocks the lady’s retreat along the f1-a6 diagonal. Black answers with a6 forcing the 9 pointer’s retreat to the b3 square inviting the fatal pin.