Ruthless City were already all-but assured of a place in the final against either arch-rivals Manchester United or Sunderland on March 2 after thrashing Sam Allardyce's side 6-0 in the first leg at the Etihad Stadium.
And the Premier League title contenders heaped more misery on the struggling London club, Negredo striking a goal in each half at Upton Park to take his tally to 23 goals for the season as Manuel Pellegrini's claimed the most emphatic semi-final victory in the Capital One Cup.