Chelsea recorded their first win under new manager Guus Hiddink as the Blues' resurgence under their new boss continued with a 3-0 win at Crystal Palace.
Oscar gave the Blues the lead in the first half before Willian and Diego Costa put Palace out of sight to complete arguably the champions' best performance of the season so far.
The victory is Chelsea's first on the road in the league since August and means Hiddink remains unbeaten after three games in charge.
It was one year to the day that Alan Pardew was appointed Palace manager and the clubs' respective reversal in fortunes since then remains remarkable given this time last year Chelsea sat top and the Eagles were in the relegation zone.
The teams' overall trajectories remain but Chelsea will take great confidence from a win that moves them up to 14th and demonstrated that European football may still not be out of reach.
Wilfried Zaha, making his 200th appearance for Palace, fizzed an early shot wide but chances were few and far between in the opening stages as torrential rain made keeping possession difficult.
Chelsea playmaker Eden Hazard only lasted a quarter of an hour as he hobbled off to be replaced by Pedro and it was Palace who settled faster, with one Jason Puncheon cross skidding to Fraizer Campbell at the back post but the striker sliced over.
A few weeks ago Chelsea, flustered by their opponents' pace in behind, might have caved but Hiddink appears to have revived some of his side's grit and resilience and instead they took the lead in the 28th minute.
Suitably it was the three players arguably who struggled most under Jose Mourinho involved, as Cesc Fabregas slid a superb through ball into Costa, who pulled the ball back for Oscar to tap home his second goal in four games.
The advantage injected confidence into the visitors, who finished the stronger before half-time as Cesar Azpilicueta chested Oscar's lofted pass into the penalty area but saw his half-volley saved by Eagles goalkeeper Wayne Hennessey.
Chelsea's ascendancy continued after the interval and Kurt Zouma should have scored when he rose above Mile Jedinak at the back post, but the defender headed over the crossbar.
Palace looked vulnerable but their best chance of an equaliser came just before the hour as Campbell played Zaha into the penalty area but the forward scuffed his finish harmlessly into the hands of Chelsea goalkeeper Thibaut Courtois.
It proved a decisive moment as one minute later a loose ball spilled out to Willian and the winger rifled it into the top corner from 25 yards to double Chelsea's advantage.
Having come close to being drawn level, the Blues were suddenly in control and six minutes later they put the game to bed as Willian's shot was weakly parried by Hennessey, allowing Costa to poke in his third goal in two games.
Palace were shell-shocked and it could have been worse at the end as Oscar saw a goal-bound shot blocked, but that was no matter for the travelling supporters who were left singing 'everything is going to be all right' when the final whistle blew.