Chelsea were made to work hard and earn their dues in a 1-0 win over West Bromwich Albion on Sunday. The victory was the Blues’ 9th consecutive triumph in the league, and takes them back to the top of the table, three points clear of Arsenal. Diego Costa was the match-winner, yet again, with an absolute beauty in the 76th minute, taking his tally in the league to 12.

The halfway mark is approaching, and Antonio Conte‘s men have shown incredible resolve and character in their resurgence. It looked like fighting for the top 4 would be their realistic target at the end of September, but now things have completely changed. Sunday’s win against Albion showed a different side to their game, as they dug deep but finally found the answer.

Here are 3 major talking points from the fascinating encounter at Stamford Bridge:

1) Chelsea look laborious at the start, couldn’t find the solution to West Brom’s disciplined approach

The Baggies were well-drilled and miserly, as can be expected from aTony Pulis side. The two wingers dropped back to operate almost as full-backs, who in turn tucked in to form a 6-man defence. Eden Hazard found it difficult to weave his magic against Craig Dawson, while Gareth McAuley and Johnny Evans were absolutely fantastic in the heart of the back-line.

At the other end of the pitch, Salomon Rondon kept David Luiz honest throughout, and even got the better of the Brazilian on more than one occasion. The Colombian came close to opening the scoring in the first half, when his shot fizzed wide of Thibaut Courtois‘ post.

All in all, the visitors were extremely solid and efficient, and Chelsea managed just one shot on target in the first half, whichBen Foster comfortably saved.

2) Conte looks for inspiration, brings on Fàbregas and Willian

A similar pattern continued at the start of the second period, and the Chelsea manager looked to change things from a tactical point of view. He brought off Pedro and Victor Moses for Willian and Cesc Fàbregas respectively. This switch saw the home side go to a more traditional 4-man defence, with Marcos Alonso playing as left-back. The two full-backs operated high up the pitch and were camped in the opposition half for long periods.

3) One mistake, and Costa pounces

The defending from West Brom had been first-class all afternoon, but fatigue was beginning to show as they approached the closing stages of the game. The levels of concentration had to be at their highest, because it was going to take just one lapse for Chelsea to capitalise. Unfortunately for them, that is exactly what happened.

McAuley looked to have a long punt downfield from Fàbregas covered, but Costa came breathing down his neck. The Northern Irishman decided to shield the ball rather than clear it, and paid the price. The Chelsea striker robbed him, ran into the box, and unleashed an unstoppable left-footed shot into the top corner.

This was his first shot on goal in the game, but that’s all that was needed to make the telling difference. Stamford Bridge exploded, and Conte‘s reaction on the sidelines told the entire story. It had been a tough and frustrating afternoon for Chelsea, but coming out with the three points in this kind of game gives them a massive boost in confidence and belief.

Chelsea next travel to Sunderland in midweek, while West Brom host Swansea City.