By Alex Stevens

Chelsea are phasing out the centre-back partnership that was the bedrock of their title win, Pedro gives the team more firepower and other things we learned from Sunday’s thriller at the Hawthorns, which ended West Brom 2 Chelsea 3.

Cahill-Terry partnership is being phased out

Yet more centre-back dramas for Chelsea. First Cahill was axed and then Terry was sent off early in the second half. For the majority of their last three halves of Premier League football, Jose Mourinho’s team have employed three different centre-back partnerships. Once a beacon of consistency, the backline is now in a state of flux. Kurt Zouma played the entirety of this clash after getting the nod to start ahead of Cahill, presumably for his greater speed across the ground. It was this lack of mobility that proved so costly for Terry when he got involved in a foot race with Salamon Rondon after 54 minutes. It was won comfortably by the striker and Terry, who was the last man, paid the price for tugging at his opponent. Referee Mark Clattenburg rightly judged it to be a professional foul and handed the Chelsea skipper a red card. Terry showed what he thought of the decision by taking an age to leave the pitch. With a suspension for the 34-year-old now imminent and a fresh offer expected for John Stones, it could be quite some time before we see him in action again.

Pedro should be a bona fide Premier League star

Starting well for your new club following a high profile transfer does not always guarantee a stellar Premier League career. Just ask Angel Di Maria. But things could not have gone better for Pedro on a debut that was hugely encouraging for the visitors. The £21.2million signing from Barcelona scored the first of Chelsea’s three goals, created the second and buzzed throughout with energy, drive and potency. He has immediately lifted the champions with his pedigree and presence.

James Morrison is an unsung hero

The West Brom midfielder shares a name with the singer-songwriter, and even similar facial features, without possessing quite his namesake’s fame. This was one of those days when the 29-year-old, a West Brom player for eight years,  deserves to be put on a pedestal. In truth, he could and should have had a hat-trick, but a magnificent save with his foot from Thibaut Courtois stopped him opening the scoring from the penalty spot. But Morrison was not put off. He showed great technique to drive home his team’s opener and then gave them hope with a fine, flicked header to double his account. He was subbed late on but this was a fine performance from a long-standing servant whose standards rarely drop.

Costa is back to his best

This was the Costa of the first half of the 2014-15 season; powerful, potent and a pain in the backside for centre-backs. Opponents know they are in for a battle when they face the Chelsea No19 but, far too often of late, it is the striker’s temper and fondness for the dark arts that have caught the eye. Costa was hardly on his best behaviour at the Hawthorns, thrusting his head in the direction of Claudio Yacob during one flashpoint before being withdrawn for his own good after 76 minutes, but he delivered a perfect example of how to lead the line away from home. He got his reward by meeting Pedro’s cross-cum-shot for Chelsea’s second, and his first of the season, but just as impressive was the way he chested a Cesc Fabregas chip into the path to assist the visitors’ crucial third goal.

Mourinho and Pulis need to tighten up their teams

With three matches of the season gone, Chelsea have conceded seven goals and West Brom six. Mourinho and Tony Pulis, bywords for organisation and resilience, must be seething at the frequency with which their teams are conceding goals. This was as open an encounter as you could wish to see, long before Terry’s sending-off had ensured a grandstand finale.  In total, the teams traded 30 goalscoring attempts, 15 apiece. Great for neutrals, not so good for managers whose fondness for a 1-0 win is George Graham-esque.