After suffering our first defeat in any competition since the end of September, Chelsea lost ground in the title race on Saturday afternoon and here we take a closer look at the numbers and talking points from our 3-2 loss to West Ham.

It was a topsy-turvy game in east London, one Thomas Tuchel’s side twice led before seeing the points slip away in the second half, with rare mistakes proving costly. Thiago Silva headed us in front before Mason Mount fired in a stunning volley to restore our advantage after Manuel Lanzini had equalised from the penalty spot following a foul from Edouard Mendy.

With a 2-1 lead at the break, the Blues were in control but Jarrod Bowen and Arthur Masuaka proved the Hammers’ heroes, condemning us to a second league defeat of the campaign. With Liverpool and Manchester City winning later in the day, it saw us drop to third in the table.

Chance comparison

Despite losing the game, the visitors came out on top in most of the key performance metrics including shots (19 to West Ham’s 11), completed passes (507 to 250) and possession (64 per cent to 36 per cent).

However, the actual quality of our big chances as measured by xG was the lowest since a narrow victory at Brentford in October, with David Moyes’s side more efficient in carving out better opportunities from their fewer attacks and coming out with a shot conversion rate of 27 per cent, almost three times that of the Blues. Part of that was also down to individual mistakes handing the hosts the initiative, including the concession of a penalty and a speculative cross from Masuaka beating Mendy late on.

As the average positions graphic below shows, our shape was a little disjointed and the wing-backs less advanced than we have normally seen this season under Tuchel, with the attacking trio of Kai Havertz, Hakim Ziyech and Mount congested into a small central pocket. West Ham matched our shape and had joy in pushing Reece James and Marcos Alonso back.

Roaming Ruben

For Ruben Loftus-Cheek, it was a third successive start and he was joined in the midfield engine room by Jorginho, who had missed the midweek win at Watford.

The pair had 170 touches of the ball between them and only James had more individually (97), with Loftus-Cheek particularly progressive with his use of possession.

The 25-year-old made four successful dribbles, as many as the West Ham team combined, completed two key passes and ended with a pass completion rate of 91 per cent, the highest in the game barring Jorginho and Issa Diop.

Letting it slip

Tuchel’s men were unquestionably in control at the break but let a half-time lead slip for the first time in the Premier League under the German. Our last such reversal came three years ago against Wolves with Maurizio Sarri at the helm, an unbeaten run of 48 league games.

It was also just the third time we have conceded more than once in a game in Tuchel’s 53 matches in charge and proved a rare defensive off day, conceding three in a match after shipping just six in 14 league outings prior this term.

Losing the duel count may have been a factor in that as the Irons beat us 17-14 in the air, 13-6 in tackles and 27-9 in clearances. Our nine corners did pay dividends though as Thiago Silva powered in the early opener, becoming our oldest ever Premier League goalscorer in the process. At the other end of the age scale, James became the youngest Blue to start a half-century of Premier League matches for the club in 12 years.

Mount's influence

After becoming the first player to hit double figures for goals under Tuchel in midweek, Mount added another to his growing tally in stylish fashion, caressing a precise volley into the bottom corner with one of our best finishes of the season to date.

His back-to-back goal-and-assist performances have taken him to 18 goal involvements under the boss (11 goals, seven assists), more than any other Chelsea player.

He was influential again at the London Stadium, taking three shots all on target, registering more touches than all but four other players on the pitch and completing four key passes, a joint game high.

Unfortunately, scoring one and teeing up another was not enough to earn a point for his team though as the Blues returned west empty-handed.