Olivier Giroud (73’) – 5. The French target man didn’t impact the game during his brief spell on the pitch. EPA
WEST BROM RATINGS: Sam Johnstone – 6. Conceded three goals under constant Chelsea pressure but also kept out a fair few chances. Reuters
Darnell Furlong – 7. Lovely headed flick-on for Bartley’s goal and stood up to Chelsea’s wide attacks in the first half. Hudson-Odoi made his task tougher in the second 45. AP
Semi Ajayi - 6. Burst of pace past Alonso prompted a booking for the Chelsea defender, who did not make it past half-time. Stood firm against Abraham's strength. AP
Kyle Bartley – 7. Scored West Brom’s third and kept Chelsea’s attacks at bay for almost an hour. EPA
Dara O'Shea – 6. Dealt well with Chelsea’s onslaught up until the visitors found a breakthrough. Getty Images
Conor Townsend – 6. Pegged back and couldn’t get forward in his wing-back role as West Brom ceded most of the possession. Reuters
Matheus Pereira – 7. Fine pass for Johnstone’s opener and produced a delightful flick which, if there was an award, would win touch of the season. A good performance. PA
Jake Livermore – 7. Provided plenty of bite in midfield during a first half when Chelsea failed to create any rhythm. PA
Romaine Sawyers – 6. A quiet game as Chelsea kept the majority of the ball. Reuters
Grady Diangana – 6. A player with plenty of skill and talent but neither were on full display on this occasion. Getty Images
Callum Robinson – 8. Well taken finish to open the scoring for West Brom before pouncing on a Silva mistake to double his side’s lead. AP
SUBS: Hal Robson-Kanu (66’) – 6. No real impact. Reuters
Matt Phillips (74’) – 6. No real impact. Getty Images
Sam Field (90’) – N/A Getty Images
CHELSEA RATINGS: Willy Caballero – 6. Not at fault for any of West Brom’s goals but hardly inspires confidence. The sooner Edouard Mendy is ready to start, the better for Chelsea. EPA
Reece James – 6. Got forward all game and provided crosses aplenty. Caught out defensively at times and was partly at fault for West Brom’s third. Reuters
Andreas Christensen – 6. More reliable than his defensive partner but hardly rock solid. AP
Thiago Silva – 5. Improved as the game went on but his miss control for Robinson’s second was a critical mistake. Not the Premier League debut he would’ve hoped for. EPA
Marcos Alonso – 2. Nightmare display. Weak header led to Robinson’s first goal and minutes later was booked. Set the tone for a disastrous 45 minutes before getting hooked. Apparently, the pitchside photographers didn’t believe Alonso’s performance even warranted a photo, so here he is against Liverpool. PA
N’Golo Kante – 6. As expected, plenty of energy from the Frenchman but struggled to impose himself on the game. Getty Images
Mateo Kovacic – 5. Uncharacteristically off the pace. Replaced at half time. Reuters
Mason Mount – 8. Great movement and finish to score Chelsea’s first to offer his side a lifeline. His low shot late on led to Abraham’s equaliser. After an anonymous first half, vastly improved after the break. EPA
Kai Havertz – 7. Coming off the back of his League Cup hat-trick, Havertz was Chelsea’s most effective midfield player during their second half fightback. A perfectly weighted one-touch pass to set up Hudson-Odoi’s finish. Getty Images
Tammy Abraham – 6. Granted, he scored the vital equaliser by tapping into an empty net, but he rarely posed much of a threat for the previous 94 minutes. EPA
Timo Werner – 5. Couldn’t make anything happen, although not through lack of trying. Saw a first half effort clip the crossbar. A frustrating evening for the German. Getty Images
SUBS: Cesar Azpilicueta (45’) – 7. Compared to the man he replaced at left-back, the Chelsea captain looked like a prime Maldini. In reality, it was a solid performance and the Spaniard brought some much-needed composure to a shambolic backline. PA
Callum Hudson-Odoi (45’) – 8. The winger was a constant menace on the left, creating chances, beating defenders, and scoring a fine goal for Chelsea’s second. Played a vital role in the fightback. EPA
Olivier Giroud (73’) – 5. The French target man didn’t impact the game during his brief spell on the pitch. EPA
WEST BROM RATINGS: Sam Johnstone – 6. Conceded three goals under constant Chelsea pressure but also kept out a fair few chances. Reuters
Darnell Furlong – 7. Lovely headed flick-on for Bartley’s goal and stood up to Chelsea’s wide attacks in the first half. Hudson-Odoi made his task tougher in the second 45. AP
Semi Ajayi - 6. Burst of pace past Alonso prompted a booking for the Chelsea defender, who did not make it past half-time. Stood firm against Abraham's strength. AP
Kyle Bartley – 7. Scored West Brom’s third and kept Chelsea’s attacks at bay for almost an hour. EPA
Dara O'Shea – 6. Dealt well with Chelsea’s onslaught up until the visitors found a breakthrough. Getty Images
Conor Townsend – 6. Pegged back and couldn’t get forward in his wing-back role as West Brom ceded most of the possession. Reuters
Matheus Pereira – 7. Fine pass for Johnstone’s opener and produced a delightful flick which, if there was an award, would win touch of the season. A good performance. PA
Jake Livermore – 7. Provided plenty of bite in midfield during a first half when Chelsea failed to create any rhythm. PA
Romaine Sawyers – 6. A quiet game as Chelsea kept the majority of the ball. Reuters
Grady Diangana – 6. A player with plenty of skill and talent but neither were on full display on this occasion. Getty Images
Callum Robinson – 8. Well taken finish to open the scoring for West Brom before pouncing on a Silva mistake to double his side’s lead. AP
SUBS: Hal Robson-Kanu (66’) – 6. No real impact. Reuters
Matt Phillips (74’) – 6. No real impact. Getty Images
Sam Field (90’) – N/A Getty Images
CHELSEA RATINGS: Willy Caballero – 6. Not at fault for any of West Brom’s goals but hardly inspires confidence. The sooner Edouard Mendy is ready to start, the better for Chelsea. EPA
Reece James – 6. Got forward all game and provided crosses aplenty. Caught out defensively at times and was partly at fault for West Brom’s third. Reuters
Andreas Christensen – 6. More reliable than his defensive partner but hardly rock solid. AP
Thiago Silva – 5. Improved as the game went on but his miss control for Robinson’s second was a critical mistake. Not the Premier League debut he would’ve hoped for. EPA
Marcos Alonso – 2. Nightmare display. Weak header led to Robinson’s first goal and minutes later was booked. Set the tone for a disastrous 45 minutes before getting hooked. Apparently, the pitchside photographers didn’t believe Alonso’s performance even warranted a photo, so here he is against Liverpool. PA
N’Golo Kante – 6. As expected, plenty of energy from the Frenchman but struggled to impose himself on the game. Getty Images
Mateo Kovacic – 5. Uncharacteristically off the pace. Replaced at half time. Reuters
Mason Mount – 8. Great movement and finish to score Chelsea’s first to offer his side a lifeline. His low shot late on led to Abraham’s equaliser. After an anonymous first half, vastly improved after the break. EPA
Kai Havertz – 7. Coming off the back of his League Cup hat-trick, Havertz was Chelsea’s most effective midfield player during their second half fightback. A perfectly weighted one-touch pass to set up Hudson-Odoi’s finish. Getty Images
Tammy Abraham – 6. Granted, he scored the vital equaliser by tapping into an empty net, but he rarely posed much of a threat for the previous 94 minutes. EPA
Timo Werner – 5. Couldn’t make anything happen, although not through lack of trying. Saw a first half effort clip the crossbar. A frustrating evening for the German. Getty Images
SUBS: Cesar Azpilicueta (45’) – 7. Compared to the man he replaced at left-back, the Chelsea captain looked like a prime Maldini. In reality, it was a solid performance and the Spaniard brought some much-needed composure to a shambolic backline. PA
Callum Hudson-Odoi (45’) – 8. The winger was a constant menace on the left, creating chances, beating defenders, and scoring a fine goal for Chelsea’s second. Played a vital role in the fightback. EPA
Olivier Giroud (73’) – 5. The French target man didn’t impact the game during his brief spell on the pitch. EPA