The introduction of Romelu Lukaku proved pivotal as Chelsea won 3-1 away to Aston Villa on Boxing Day, Thomas Tuchel's side getting the victory after dominating possession for long spells throughout the second half.
The Blues had fallen behind to a Reece James own goal, but they responded just six minutes later when Jorginho converted from the spot after Callum Hudson-Odoi, who was excellent on the night, was taken down in the area by Matt Cash.
Lukaku came on at half-time and added a focal point to Chelsea's wide play, with Hudson-Odoi and Christian Pulisic returning to their more supportive roles. As Chelsea applied the pressure, Lukaku got in front of Tyrone Mings to convert a Hudson-Odoi cross with a glancing header.
Lukaku then earned a penalty in injury time, which Jorginho converted to extend Chelsea's advantage. The much-needed win reduced the gap between Chelsea and Premier League leaders Manchester City to six points.
Chelsea dominated possession and despite falling behind they kept going. Their response to going a goal down will particularly have pleased Tuchel, as they managed to get back into the game after just six minutes. Lukaku will be delighted to be back and immediately in the swing of things in front of goal, too.
Villa were quick on the transition and Chelsea were often found stretched with the home side dangerous on the break. Moreover, despite having had more of the possession, the Blues didn't trouble Emiliano Martinez in the Villa goal as much as Tuchel would have probably liked.
Manager rating out of 10
8 -- Tuchel's introduction of Lukaku changed the game, with the Belgian proving to be an effective focal point, which had been sorely lacking in the first half, for visiting Chelsea.
Player Ratings (1-10; 10 = best, players introduced after 70 minutes get no rating)
GK Edouard Mendy, 6 -- Was caught out when Matt Targett's deflected cross wrong-footed him and flew into the net, the ball going off his fingertips. He soon put it behind him though and rushed out quickly to deny Ollie Watkins soon after.
DF Marcos Alonso, 6 -- The Spaniard didn't find as much space on the left as James on the right, but he troubled Villa with of teasing crosses in particular, with Targett denying Mason Mount at the far post on one particularly nice ball from Alonso.
DF Reece James, 6 -- Enjoyed oodles of space at times such was Villa's narrow approach, but his final balls from the right often let him down and was guilty of the own goal that gave the hosts their opener.
DF Thiago Silva, 8 -- Showed excellent positioning in the first half to clear any balls into the box. Chelsea were stretched at times, but the Brazilian showed excellent composure to clear the lines. Was forced off in the second half with a knock.
MF Jorginho, 7 -- It's now five and six penalties in a row for Jorginho, who calmly tucked home after Hudson-Odoi was upended, and then when Lukaku was fouled. The Italy international was key to transitioning the ball forward for the visitors.
MF N'Golo Kante, 6 -- As hard working as ever, though his impact was only noted once he was substituted, as Chelsea found themselves under some pressure in his absence.
MF Trevoh Chalobah, 6 -- Sometimes caught out of position when Villa broke, but he showed good awareness to track back when needed. Made way for Lukaku at the break.
MF Mason Mount, 6 -- Was first to come close to troubling Martinez when his cross-turned-shot midway through the first half had the Villa keeper scrambling. He then had a glorious chance in the second half but snatched at it when Lukaku and Pulisic were in a better position to score.
MF Callum Hudson-Odoi, 8 -- Was influential when Chelsea got back into the game. His driving run caught Cash flat-footed, and he was brought down for a spot kick, which Jorginho converted. His cross set up the Lukaku winner and he had a late chance to score that Martinez saved well.
FW Christian Pulisic, 6 -- Had a very quiet first half when leading the line, and so fell into a more withdrawn role on the right following Lukaku's arrival at half-time. The switch suited him, and he was more effective after the break.
FW Romelu Lukaku, 8 -- It took Lukaku just six minutes to make an impact, the Belgian's movement seeing him get in front of Mings to head home with a lovely glancing redirection of Hudson-Odoi's cross to the far post.
DF Andreas Christensen, 5 -- Silva had been a calming presence at the back, but luckily the Blues weren't stretched following Silva's departure.
MF Mateo Kovacic, 5 -- Chelsea lost control of the game following Kante's exit, with Kovacic unable to hold the midfield together.