Neil Warnock has claimed even his West Ham counterpart Manuel Pellegrini could not understand how Cardiff City lost out at West Ham.
Joe Ralls missed a first-half penalty at London Stadium, with West Ham taking full advantage with three goals in a 12-minute burst after the break.
Lucas Perez, on for the injured Marko Arnautovic, scored twice and Michail Antonio added a third as West Ham seized control of the game, ensuring Josh Murphy’s stoppage-time header was a mere consolation.
But Warnock revealed his bemusement as to how Cardiff slumped to a fifth-successive away defeat, meaning they remain two points above the relegation places.
“I don’t know how we lost the game, let alone lost it 3-1,” Warnock, whose side face fellow strugglers Southampton next time out, told BBC Sport.
“I called Manuel over and said, ‘how are we losing 3-0?’. He said: ‘I don’t know’.
“The defending for the goals we have conceded this season has been appalling and we need to work hard on the training ground to eliminate these things.
“You can’t fault them, we have won three games from behind, it shows the character, we have just got to stop making silly mistakes. Three mistakes for goals and that’s cost us.”