Thomas Tuchel trying to solve Chelsea's attacking puzzle ahead of Man Utd and Liverpool meetings

Chelsea produced another impressive defensive display in Tuesday's Champions League win over Atletico Madrid. They have now kept six clean sheets in eight games under Thomas Tuchel. It's as many as they managed in the last 16 under Frank Lampard.

Atletico were limited to six shots, none of them on target, and it's been a similar story for Chelsea's Premier League opponents. Since Tuchel's appointment, Chelsea have faced the fewest shots in the division and recorded the lowest expected goals against total too.

Little wonder, then, that they are racking up the clean sheets. Tuchel has made defensive stability a priority since his arrival, switching to a back three and making Chelsea more robust by deploying two defensive midfielders rather than one.

At the other end of the pitch, however, there is still much work to do.

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Olivier Giroud's overhead kick proved decisive against Atletico and Chelsea's overall performance in Bucharest was certainly a step in the direction. But Tuchel is still grappling with many of the same issues as his predecessor when it comes to their attack.

Chelsea hoped their recruitment in that area last summer - Kai Havertz, Timo Werner and Hakim Ziyech arrived at a combined cost of £154m - would transform them into title challengers.

But Lampard couldn't find a way to fit the pieces together and it's proving tricky for Tuchel too. The 47-year-old has cut an exasperated figure at times, reacting angrily when moves have broken down and showing his ruthless side with some of his substitutions.

Callum Hudson-Odoi felt his wrath during the 1-1 draw with Southampton last Saturday when he was withdrawn only 31 minutes after coming off the bench, while Tammy Abraham was hooked at the interval for the second time in three games.

Tuchel was critical of both players after the game and also addressed Chelsea's broader offensive issues.

"We think day and night about scoring and creating chances. We play high up the pitch and given the statistics from the last matches, I know we don't score enough for the number of touches in the box, the number of shots, the number of chances we're creating."

Tuchel went on to bemoan Chelsea's "lack of precision" and "lack of quality in decision-making" in the final third. "Today I did not feel in the last 20 meters that we would kill the game when it was there to be done," he added.

Lampard could be heard making similar comments throughout his tenure and despite Chelsea's recent defensive improvement and the dramatic upturn in results over the last few weeks, the side's attacking output has in fact dipped since Tuchel's appointment.

Chelsea are enjoying more possession and getting into the opposition box more frequently, but their scoring rate has dropped and so have their numbers for expected goals and shots on target.

Chelsea are struggling to convert their possession into high-quality chances, in other words, and they are not helped by the wasteful finishing reflected in their falling shot accuracy.

Tuchel will hope Giroud is able to build on his match-winning display against Atletico in the remaining months of the season but the bigger priority is to coax more from the young players around him.

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Mason Mount has, to his credit, picked up where he left off under Lampard, scoring in the 2-1 victory over Sheffield United and winning and converting Chelsea's penalty in Saturday's 1-1 draw with Southampton. But the rest are yet to catch the eye.

Injuries have hampered Havertz, Ziyech and Christian Pulisic, of course, but all three are fully fit now. Tuchel must find a way to get the best out of them and the same is true of Werner.

The 24-year-old has played more Premier League minutes than any other Chelsea attacker under Tuchel. Having been shunted between positions under Lampard, he has at least been given a more focused role, in the inside-left channel, under Tuchel.

Werner thrived in a similar position at previous club RB Leipzig and Tuchel's counter-pressing system should suit him too. But right now his performances remain erratic and his output low. Werner ended a 14-game barren run with his goal against Newcastle but there is still a sense that he is finding his feet at Chelsea.

It is likely that Werner and his team-mates will have a new central striker to combine with next season. Giroud, 34, is nearing the end of his contract and Chelsea are said to be among the leading candidates to sign Erling Haaland from Borussia Dortmund.

But until then it is Tuchel's task to get the side firing using the players he already has, and to turn a collection of talented individuals into a functioning unit.

Chelsea are already making progress, of course, having climbed to fifth in the Premier League since Tuchel's appointment. But they now face a pivotal run of games against Manchester United, Liverpool, Everton and Leeds before the second leg of their Champions League last-16 tie with Atletico.

Tuchel will hope to make it as difficult as possible for those sides to break Chelsea down and recent performances provide plenty of encouragement in that regard. But the next step is to complement their defensive solidity with the kind of attacking potency the club had in mind after last summer's recruitment drive.

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