Chelsea moved six points clear at the top of the Premier League as Cesc Fabregas’ first-half goal beat a stubborn Sunderland at the Stadium of Light.
Fabregas steered into the far corner from the edge of the box as the Blues recorded a 10th consecutive league victory.
Sunderland keeper Jordan Pickford saved from former Black Cat Marcos Alonso and Willian to prevent Chelsea from winning by a bigger margin.
The hosts, who had set up to try to nullify their opponent’s attacking strength, had few chances although they could have snatched a point in injury time but Thibaut Courtois superbly denied Patrick van Aanholt.
It was a hard-fought and important win for Chelsea after Arsenal slipped up against Everton on Tuesday and means Antonio Conte’s side will be top of the table at Christmas.
A key element of Chelsea’s run of recent victories has been consistency with Conte having named an unchanged side in eight of the nine games prior to the trip to Sunderland.
Liverpool boss Jurgen Klopp had recently suggested that Chelsea’s good run could falter when either Eden Hazard or Diego Costa picked up an injury, and Wednesday’s game provided an opportunity to see whether that would be the case.
Hazard did not travel after picking up a knock in Chelsea’s 1-0 win over West Brom at the weekend, so he was replaced by Willian. Conte also took the opportunity to rest Nemanja Matic as Fabregas made his first start since 3 December.
Initially, Chelsea appeared to miss Hazard’s creativity as they struggled to find a way to break down a packed Sunderland defence, but Fabregas highlighted the Blues’ strength in depth.
As Sunderland’s seven-man defence frustrated the visitors, Fabregas somehow managed to find the gap to sneak a shot into the far corner and ultimately give Chelsea victory.
Chelsea have kept a clean sheet in five of their previous seven games but their inability to put the game out of Sunderland’s reach was a cause for concern for Conte.
For the third time in four games, they won by a single goal margin and Conte is now keen to see his side improve their finishing.
“When you have the possibility to kill the game you must kill the game,” he said. “We had this possibility but we didn’t and at the end Courtois made a good save. I hope in the future we can improve.”