Arsenal reached the League Cup semi-finals after edging Crystal Palace 8-7 on penalties on Tuesday, with goalkeeper Kepa Arrizabalaga saving the decisive spot kick from Maxence Lacroix.
It was a difficult night for Palace defender Lacroix, who had earlier put through his own net in the 80th minute to give Arsenal the lead.
Palace captain Marc Guehi rescued his side in stoppage time, nodding home from a free-kick knockdown to force a 1-1 draw and send the tie to a shootout.
All penalties were converted until Lacroix’s miss, which sealed Arsenal’s place in the last four, where the Premier League leaders will face Chelsea.
Arsenal next hosts Brighton & Hove Albion in the Premier League on Saturday, while eighth-placed Palace welcomes Tottenham Hotspur on Sunday.
Manager Mikel Arteta praised his side’s resilience, while Palace boss Oliver Glasner took encouragement from his team’s second-half display.