Jana Leitzig rewarded Leicester manager Willie Kirk's gamble in bringing her on specifically for a penalty shootout as they beat Manchester City in the League Cup.
Leitzig was brought on to replace fellow goalkeeper Lize Kop in the 93rd minute as penalties loomed.
And she saved from Steph Houghton in sudden death to give Leicester the victory.
Leicester had allowed a two-goal lead to slip in normal time, with Janice Cayman and Sophie Howard scoring to put them clear in the first half.
Manchester City boss Gareth Taylor had made nine changes to the 11 that started Sunday's 3-1 Women's Super League win against Manchester United at a packed Old Trafford, and his side struggled to adapt.
Taylor brought Alex Greenwood, Lauren Hemp and Yui Hasegawa off the bench as City emerged for the second half and that trio had an immediate impact.
The home side, who had won 1-0 at Leicester in the WSL in October, pulled a goal back four minutes into the second half with Venezuela international Deyna Castellanos scoring her first goal of the season.
Laura Coombs pulled the four-time League Cup winners level with 20 minutes left to play.
Both Manchester City and Leicester missed two of their opening five spot kicks - Castellanos and Mary Fowler failing to convert for the hosts, while Lena Petermann and Cayman missed for the Foxes.
Howard made no mistake for Leicester as the shootout entered sudden death and Houghton was then denied by Leitzig.
The victory keeps Leicester third in Group B, one point adrift of Manchester United and two shy of leaders City.
Elsewhere on a busy night of League Cup action, Manchester United saw off Liverpool 1-0 thanks to a first half goal from Nikita Parris at Prenton Park.
Aston Villa demonstrated their early-season struggles are firmly in the past as they made it four wins on the bounce with a 7-0 demolition of Championship outfit Blackburn.
Rachel Daly and Alisha Lehmann each scored twice with Ebony Salmon, Mayumi Pacheco and Simone Magill also getting on the scoresheet.
Villa are top of Group B with the maximum six points and have scored 12 goals without conceding.
All four teams in Group C featured on Wednesday as Crystal Palace beat Championship rivals Watford 3-0 and London City Lionesses edged a 1-0 win at Lewes.
Bristol City are the first team to be eliminated from the competition after going down 3-0 at Tottenham.
The win for Tottenham propels them above Southampton to the top of Group D.
Brighton earned revenge for their WSL loss against West Ham in October by sealing a 3-1 win at The People's Pension Stadium.
It is successive victories for the south coast club to put them at the top of Group E, while Charlton, who beat Birmingham 1-0, are second in the standings.