Chelsea have started the season without a first-team striker... and the question is: Do they need one?
Romelu Lukaku's £97.5m return last summer was meant to be the missing piece in the jigsaw but after only eight Premier League goals he has returned to Inter Milan on loan.
Timo Werner, who often played out wide but could also play as a striker, has also gone back on loan to his old club, RB Leipzig.
Both players scored last Saturday on their returns to their previous clubs.
That leaves only 20-year-old Albania international Armando Broja - who is not likely to be a regular starter - as a Blues striker.
So who could Chelsea sign? Will Broja get a chance? Or will they go through the season without a number nine?
Chelsea are being linked with Barcelona striker Pierre-Emerick Aubameyang.
Only four players have scored more Premier League goals than Aubameyang's total of 68 in the period since 31 January 2018 - the date he joined Arsenal.
The 33-year-old former Gabon international scored 92 goals in 163 games in all competitions for Arsenal but left in February after falling out with boss Mikel Arteta.
He joined Barca, scoring 13 goals in 23 games, but could now be allowed to leave them after they signed Robert Lewandowski.
Aubameyang and Chelsea boss Tuchel worked together at Borussia Dortmund to great effect in 2015-16 and 2016-17.
Tuchel recently said: "Some players stay your players because you were very, very close and Auba is one of those players."
The striker scored 79 goals in 95 games in two seasons under the German, 38 goals more than he bagged under any other manager.
Only four players have scored more Premier League goals than Aubameyang since he joined Arsenal on 31 January 2018
Former Republic of Ireland striker Clinton Morrison told BBC Radio 5 Live: "Chelsea would be the right club for Aubameyang. A manager he respects will only help him.
"They have made outstanding signings and if they get Aubameyang, he will score goals so I wouldn't write them off [from being contenders] this season if that happens."
Ex-England international Matt Upson is "not totally convinced" though.
"Auba's stock wasn't so high because of issues around Arsenal," he said. "You know he will bring goals though. Would Chelsea not want younger players?
"If they want to be competitive with the very best, they have to score 80 or 90 goals or more. They don't have that at the moment. If Aubameyang is that man, then good luck to them."
Armando Broja has come off the bench in both of Chelsea's Premier League games this season
Chelsea do actually have a striker in their squad - but the question is will he get the opportunity?
Albania international Broja, who was born in Slough, has been on the books at Stamford Bridge since 2009.
Last season he went on loan to Southampton and scored six goals in the Premier League and nine in all competitions.
Only Mason Mount (11), Lukaku and Kai Havertz (eight each) scored more than six league goals for Chelsea last season.
Broja would give Chelsea a totally different option too. He won 88 aerial duels in the league last season - with Lukaku top of the Blues forwards on 51.
The youngster also completed more dribbles - 88 - than any of the Blues front line.
Broja, whose pre-season was cut short by injury, has come on for Havertz in Chelsea's first two games of the season - a 1-0 win over Everton and 2-2 draw with Tottenham.
Former West Ham defender Upson said on BBC Radio 5 Live: "He has that young, fearless attitude and if he can handle that magnitude and pressure he can be the answer right there. He could grow into something special."
Broja has been linked with Newcastle and Everton, which would leave the club with no striker at all, although Tuchel says he expects him to stay.
Raheem Sterling often played in a strikerless team at Manchester City
Manchester City proved last season you can win the Premier League title without a striker - although they have signed two this summer in Erling Haaland and Julian Alvarez.
One of their three players to hit double figures in the league last season, Raheem Sterling, has joined Chelsea this summer for £50m.
He has experience of playing in the 'false nine' role - as does Havertz, who has done it regularly for the Blues over the past two seasons.
After Sunday's 2-2 draw with Tottenham, ex-West Ham midfielder Nigel Reo-Coker said: "It's a big ask to ask Sterling to play in that role and, against some of the teams they will face, I just don't think he's going to get a lot of joy.
"Chelsea need someone like [former striker Didier] Drogba - that figure up there scoring goals, just to bear the burden and be that real number nine."
Mount, Christian Pulisic, Hakim Ziyech and Callum Hudson-Odoi are other attacking - but not striking - options.
Chris Sutton, who scored three goals for the Blues in 1999-2000, added: "I thought Lukaku would make the difference but he didn't. Havertz is not an absolute natural. They're all good footballers but where is the finishing touch?"
The Blues are currently trying to sign Everton forward Anthony Gordon - with a £45m bid turned down - but the England Under-21 international plays out wide rather than as a striker.
Ex-England goalkeeper Rob Green, who ended his career at Stamford Bridge in 2019, told BBC Radio 5 Live: "Is Gordon going to get in the starting 11? I think the money could do better elsewhere."
BBC Sport's Alistair Magowan said: "Tuchel is keen on adding intensity to his team, and his attack especially, hence why he has signed Sterling and is keen on Gordon.
"It is also why Timo Werner has gone, and why Christian Pulisic, Hakim Ziyech and Callum Hudson-Odoi could all depart on loan.
"That will freshen up the attack and instil the type of opposition-half pressing that Tuchel seeks but will it mean Chelsea are more effective if it is done without strikers? That remains doubtful, which makes Broja's departure unlikely and adding another striker a more realistic option."
Premier League goals scored by the past 13 Chelsea number nines (while they were wearing that number)
Chelsea do not have a number nine this season - literally - after the departure of Lukaku. It is the fourth time this century that they go into a season with nobody having that shirt number.
"People tell me it's cursed," boss Thomas Tuchel joked earlier this month.
"Players sometimes want to change numbers. But, surprisingly, nobody wants to touch it."
In the last 20 seasons when somebody has had the number nine shirt for Chelsea, they have only scored a combined 150 Premier League goals - an average of 7.5 a season.
Sutton (one), Mateja Kezman (four), Franco di Santo (zero), Radamel Falcao (one), Gonzalo Higuain (five) and Lukaku (eight) are among the strikers to wear the shirt for one season and fail to reach double figures.
Nobody scored a league goal wearing the number nine between Hernan Crespo in 2005-06 and Fernando Torres in 2010-11.
If Chelsea do sign a striker, might they take another number?