Lacroix’s own goal put Arsenal ahead with 10 minutes left at the Emirates Stadium before Marc Guehi snatched Palace’s stoppage-time equaliser in the 1-1 draw.
That set the stage for a shoot-out in which both teams scored their first seven penalties.
William Saliba converted Arsenal’s eighth kick and Kepa dived to his right to save Lacroix’s effort and secure an 8-7 victory.
It was a cathartic moment for the Spanish goalkeeper, who infamously refused to be substituted before Chelsea’s League Cup final penalty shoot-out defeat against Manchester City in 2019.
Kepa also missed a spot-kick in the 2022 League Cup final shoot-out loss to Liverpool.
The Gunners will play London rivals Chelsea in the semi-finals over two legs in January and February, with Manchester City facing holders Newcastle in the other last four clash.
Arsenal are into the League Cup semi-finals for a second successive year as they chase their first trophy since winning the FA Cup in 2020.
The north Londoners have only won the League Cup twice, with their last triumph coming in 1992-93, before any of their current squad were born.
After celebrating Christmas on Thursday, Mikel Arteta’s men will turn their attention back to the title race with home games against Brighton and third-placed Aston Villa to close out 2025.
Winning their first English title since 2004 is clearly Arsenal’s main aim this season, but lifting the League Cup in March would be a significant boost to a club starved of silverware in recent years.
Thrashed at Leeds in the Premier League on Saturday, Palace were playing their third game in six days after a fixture pile-up caused by their involvement in the Uefa Conference League. (AFP)
