Timo Werner's woes epitomise Chelsea's problems - but what are reasons for his struggles?

Frank Lampard had no choice but to change things at half time. With Chelsea second best and 2-0 down to relegation-threatened Arsenal after 45 minutes, something different was required. Jorginho for Mateo Kovacic was a like-for-like change, but the introduction of Callum Hudson-Odoi meant an attacker had to be withdrawn. Timo Werner was the one hooked.

The £47.5 million striker was signed in the summer to be Chelsea’s main man. The figure around which Lampard would build his team, certainly in an attacking sense. Werner scored 28 goals in 34 Bundesliga games for RB Leipzig last season and so there was a belief the German would help the Blues chase silverware.

That Werner, and not Tammy Abraham, was the attacker substituted for Hudson-Odoi at half time against Arsenal said a lot about how the 24-year-old is struggling to live up to his billing. While Werner initially looked to have settled quickly in his new surroundings, his recent performances have raised questions.

Werner hasn’t found the net for Chelsea since the 4-1 win over Sheffield United in early November. Since then, he has gone 10 games in all competitions without scoring. In that time the German has taken no fewer than 20 shots and spurned eight big chances, as they are classed. This is far from the sort of form Chelsea expected for their money.

As many big-name strikers have flopped at Stamford Bridge as have succeeded in the Roman Abramovich years. For every Didier Drogba or Diego Costa, there has been an Alvaro Morata or Fernando Torres. The payment of a large transfer fee is no guarantee that a centre-forward will thrive in a Chelsea shirt.

The manner in which Werner is underwhelming marks him out as different, though. He has been presented with chances. Lots of them. To modify a cliche, most concerning for a striker is when the opportunities don’t come at all. That has not been the case for Werner. It is, in fact, the number of chances he is spurning that surely worries Lampard most. Nobody in the Premier League can miss a sitter like him.

Wastefulness was an element of Werner’s game for RB Leipzig. He is of that class of striker that needs three good chances to score one. Werner tends to get by on the sheer number of opportunities he pitches up on the end of. At what point, however, does wastefulness begin to become more than just a feature of the German’s game? At his current rate, Werner’s chance to goal ratio is closer to 20 to one than three to one.

Positionally, Werner might argue he isn’t being harnessed correctly. Originally seen as Abraham’s replacement, the 24-year-old has been frequently deployed alongside the Englishman. And it’s Abraham who has been used through the middle with Werner in a wider position. While Julian Nagelsmann used the player in this way on occasion for RB Leipzig, it’s not what most envisaged for Werner at Stamford Bridge.

Logic seemed to suggest Lampard would return Werner to a central role once Christian Pulisic returned to fitness, but the German continues to be used in a position on the left side. With the introduction of Hudson-Odoi against Arsenal, Lampard rebalanced his attack, moving Pulisic to the left from the right. Chelsea were more effective with two natural wide men flanking Abraham as a more orthodox attacking apex. This doesn’t bode well for Werner, who needs a more specific support system than Abraham.

Competition for a place in the Chelsea attack this season is stiff. Lampard has several options and this depth gives his side a chance at the top end of the Premier League table. It also, however, has clouded Lampard's vision. This is a team still lacking an identity and an overarching purpose.

Werner epitomises this. His speed in transition and intelligent movement means Chelsea should be among Europe’s most devastating attacking outfits, but his uneven nature has prevented Lampard from leaning fully into the strengths of his £47.5 million frontman. As long as Chelsea are hedging their bets with Werner, there is unlikely to be a payout.