Crystal Palace substitute Marco Reich claimed the only goal of the game as his side beat Coventry to reach the third round of the Carling Cup.
Reich struck after 67 minutes, steering Aki Riihilahti's cross past goalkeeper Clayton Ince.
Wayne Andrews twice went close in the second half for Palace but shot wide on both occasions.
Substitute Kevin Thornton almost snatched an equaliser for Coventry right at the end but Palace held on.
Crystal Palace: Speroni, Butterfield, Fitz Hall, Hudson, Fray, McAnuff (Berry 85), Riihilahti, Togwell, Danze, Andrews (Grabban 85), Black (Reich 56).
Subs Not Used: Kiraly, Borrowdale.
Goals: Reich 67.
Coventry: Ince, Impey, Whing, Page, Watson, Hughes (Scowcroft 71), Doyle, Osbourne (Thornton 83), Jorgensen, McSheffrey, Morrell (Adebola 77).
Subs Not Used: Webb, Davis.
Ref: P Taylor (Hertfordshire).