Chelsea survived a major scare to secure a 3-2 win at Hull City and restore their six-point lead at the top of the Premier League.
Chelsea, who have a game in hand on second-place Manchester City, had looked to be on course for a routine victory when Eden Hazard crashed home an opener inside two minutes and Diego Costa doubled their advantage with another impressive strike on 10 minutes.
However, there had been an early warning sign for the visitors when Abel Hernandez was denied by Thibaut Courtois after going clean through, and Ahmed Elmohamady was able to reduce the deficit when turning home Andrew Robertson's cross on 27 minutes.
Hull, who went into the game just three points clear of the relegation zone, found an equaliser moments later when Courtois' loose touch set up Hernandez for the simplest of finishes.
The home side then looked the more likely to force a winner, and Courtois was forced into an excellent triple save with 64 minutes on the clock, but Chelsea restored their advantage on 77 minutes when Loic Remy's shot somehow found its way past Allan McGregor.
Hull battled in search of an equaliser, and Hernandez looked to have a chance in the dying seconds, but Courtois claimed the ball and Chelsea left the KC Stadium with the three points.
The result strengthens Chelsea's grasp on the title and does little for Hull's fight against the drop, though Steve Bruce's men at least showed heart for the struggle ahead.
That was not the case when Chelsea took the lead with embarrassing ease in just the second minute.
Hazard was the most alert man on the field, collecting Costa's pass and charging towards goal as the entire Hull team, most notably Gaston Ramirez and Paul McShane, backed away and allowed him to wind up as he approached the area.
His rasping shot zipped past McGregor and kicked off a breakneck period of scoring in style.
Hull should have equalised moments later, Hernandez going one on one with Courtois after Dame N'Doye's clever flick on. He made a clean connection with his shot but Courtois, having narrowed the angle, spread himself to make a vital save.
Chelsea cashed in with their second, Costa collecting Cesc Fabregas' ball before darting into the left channel.
He appeared to have lost his shooting angle but cut back, evaded Michael Dawson and Alex Bruce, and bent a stunning effort across McGregor and in off the far post.
Hull might have crumbled and it briefly seemed certain that they would, but instead they switched from 3-5-2 to 4-4-2 and fashioned a rousing comeback.
The graceful N'Doye worked Courtois with a free kick then headed the resulting corner straight at the Belgian as Chelsea's back four began to fray at the seams.
Chelsea threatened a third, Costa heading over from Filipe Luis cross, but Hull's appetite only increased. They needed a moment of inspiration to get on the board and Robertson provided it.
The Scot raced past Willian and Branislav Ivanovic with an electric run down the left then served up a wonderful cross that snaked across the six-yard line and into Elmohamady's path.
His conversion sent the stadium in raptures and just a minute later Hull had their second. Courtois claimed the assist this time, dealing calamitously with Ivanovic's back pass as he clumsily presented Hernandez with an unmissable gift.
The Uruguayan, having not scored since October, rolled home as the men in Blue looked on in open-mouthed amazement.
For the next 15 minutes Chelsea were on the ropes -- Ivanovic, Ramires and Gary Cahill all contributing to a huge error count -- but David Meyler and Ramirez sent the best chances well wide.
The visitors were immediately improved after the break -- Jose Mourinho presumably having had plenty to say for himself -- with Hazard and Costa immediately causing consternation in the Hull defence.
There were signs of nervous tension, though, Costa tussling with Jake Livermore in none too friendly fashion.
Hull were also eyeing three points and Courtois went some way to paying back his debt to the side with a stunning triple save in the 64th minute.
Elmohamady, Livermore and Ramirez all drilled shots goalwards in the space of 10 frantic seconds and each time Courtois was equal to the challenge.
Costa's day ended in apparent discomfort, the striker giving way for Remy. It proved a precipitous change, with the Frenchman turning match-winner instantly.
Chelsea broke with a precision that had eluded them since the early exchanges and when Willian picked out Remy in the middle a goal seemed certain.
He shot a shade too close at McGregor but with the Scot mid-dive, the ball ricocheted off his legs and over the line