Chelsea needed a penalty shoot-out for the second round running as they progressed into the EFL Cup quarter-finals with a 4-3 win over Southampton after a 1-1 draw at Stamford Bridge.
Reece James scored the winning spot-kick against Aston Villa in round three, and it was the wing-back who netted the decider again on Tuesday.
Once more without the injured strike duo of Romelu Lukaku and Timo Werner, Chelsea went ahead through Kai Havertz, but Che Adams hit back early in the second half.
Kepa Arrizabalaga and Fraser Forster both then saved a penalty each in the shoot-out, yet it was ultimately Will Smallbone's miss that proved costly as the five-time winners progressed.
Chelsea had set the tone when Ross Barkley delivered a teasing corner from which Saul Niguez forced Forster into a fine stop in the sixth minute.
Havertz twice went close before he punctured Southampton's resolve on the cusp of half-time when a defensive lapse allowed the Germany international to head home Hakim Ziyech's corner.
That lead lasted only two minutes into the second half, however.
Malang Sarr's error was pounced upon by Kyle Walker-Peters, whose strike squirmed beyond Kepa and into the path of Adams for a tap-in.
Where Kepa failed at one end, Forster succeeded at the other, preventing Havertz from immediately restoring Chelsea's lead.
Both goalkeepers had to be at their best in stoppage time to force penalties, Kepa saving from Lyanco and Mohammed Salisu before Forster kept out Sarr's effort.
Then, Kepa tipped Theo Walcott's spot-kick onto the post before Forster denied Mason Mount to cancel out Chelsea's advantage, only for Smallbone to blaze his penalty over, leaving James to coolly settle matters again.
He just loves a shootout, doesn't he! = pic.twitter.com/h1i4DyBXga Chelsea FC (@ChelseaFC) October 26, 2021
What does it mean? History bodes well for the Blues
Unlike in their hammering of Norwich City on Saturday, Thomas Tuchel's side did miss the firepower of Lukaku up top, but they got the job done in the end.
Chelsea had slumped out on penalties at this stage last season, to Jose Mourinho's Tottenham, but put that ghost to rest. They have now progressed from all three of their EFL Cup ties against Southampton. The previous such meeting had come in 1997-98 – the Blues winning 2-1 at Stamford Bridge en route to lifting the trophy.
Goalkeepers stand tall
Although Kepa will be disappointed by his efforts for Southampton's equaliser, Chelsea's goalkeeper had another solid game as he continues to excel in a back-up role to Edouard Mendy.
He made an impressive six saves, though that was a tally that was more than doubled by his counterpart Forster, who pulled off 13 stops in total, including from excellent efforts from Saul in each half and a sharp save from Sarr late on.
Smallbone left wondering 'what if?'
Smallbone could have put Southampton ahead with his first touch after coming on from the bench, if not for Kepa's reactions from the midfielder's header.
The youngster stood up to take a spot-kick, yet never looked like he had the required composure, and sure enough lashed his effort well over the bar.
Away games follow for each of these sides in the Premier League. Chelsea travel to Newcastle United, while Southampton face Claudio Ranieri's Watford.