Branislav Ivanovic headed in a late winner for Chelsea as they claimed a 2-1 Premier League victory at Southampton, whose mammoth run without conceding finally came to an end.
Ronald Koeman's men went into Saturday's match at St Mary's Stadium on a run of six league games unbeaten and six consecutive clean sheets.
They looked solid for much of the encounter with Guus Hiddink's rejuvenated Chelsea, with goalkeeper Fraser Forster reaching 667 minutes of top-flight football without conceding to set a new club record.
Shane Long then opened the scoring courtesy of a defensive error at the other end, taking full advantage of a poor header from Chelsea left-back Baba Rahman with a 42nd-minute strike that looked like it would prove decisive.
However, Southampton's backline fell asleep in the 75th minute, allowing Cesc Fabregas to level as Forster was beaten after 708 minutes with a cross-cum-shot.
And there was last twist in the tale, with Ivanovic meeting Willian's corner with a powerful header to complete a dramatic turnaround with one minute remaining.
Hiddink stuck with the same team that hammered Manchester City 5-1 in the FA Cup but Chelsea were dealt a blow inside six minutes when Pedro sustained a suspected hamstring injury and was replaced by Oscar.
Southampton had the better of much of the first half, although Forster was forced into action in the 26th minute, making a comfortable save from Oscar's low drive.
Charlie Austin curled wide at the other end before Forster took possession of Southampton's top-flight record for not conceding as the game passed the 34-minute mark.
Long then provided more for Southampton to celebrate, racing through on goal after Rahman inadvertently headed the ball into his path and coolly lofting the ball over Thibaut Courtois.
Chelsea started the second half the brighter, John Obi MIkel heading wide in the 53rd minute after Southampton failed to clear from a corner.
More good attacking play from Chelsea went to waste five minutes later, Diego Costa miscuing a volley at the far post as he sought to convert from Eden Hazard's superb right-wing delivery.
Long limped off for Southampton, who were aggrieved not to have been awarded a penalty in the 70th minute when Gary Cahill appeared to handle the ball in a challenge with Austin.
And Martin Atkinson's decision to wave away those claims was made more pivotal soon after as Fabregas curled beyond a stricken Forster following good work from Costa.
Willian fired narrowly wide nine minutes time, but saw his superb set-piece delivery converted emphatically by Ivanovic to seal the points and extend Chelsea's unbeaten Premier League run to 11 games under Hiddink.
Key Opta stats:
- Shane Long has scored in back to back Premier League games for the first time since he did so for Hull City in February 2014.
- Long has scored four Premier League goals against Chelsea, his second favourite opponents behind Aston Villa (five).
- Cesc Fabregas scored just his third goal in his 40th appearance this season and his first away from Stamford Bridge since scoring at QPR in April 2015.
- Reigning champions Chelsea have now won back-to-back games for the first time this season and the first time since May 2015.