Where is Mesut Ozil?
It must be a question Arsenal boss Unai Emery is getting tired of answering. Or, sort of answering.
The German midfielder has made just one Premier League start for Arsenal this season and has now been left out of the Gunners' last four matchday squads.
On Monday, his absence prompted more questions, with Arsenal badly lacking any creativity as they fruitlessly tried to break down a solid Sheffield United defence.
In the end, the Blades won 1-0 while Arsenal slumped to another defeat on the road.
Asked by BBC Sport if Ozil was available, Gunners boss Unai Emery simply replied with: "He can help us, yes."
BBC Radio 5 Live summariser Chris Sutton, however, believes Emery should be more forthcoming.
"It would be nice if Unai Emery just came out and said and then we would know instead of us guessing," he said.
"Is it a lack of commitment? We know he's a quality player but do we think he's lost his guile? His awareness? His touch?
"Of course we don't - so what's the problem?"
That, it seems, is the question on many people's lips.
Why has he not played this season?
Since joining Arsenal six years ago, Ozil has missed 101 games for the Gunners but has only had one major injury in that time.
Most of his absences have been explained away by illness or minor niggles, while he missed Arsenal's season opener against Newcastle along with team-mate Sead Kolasinac because of security concerns after they were involved in an attempted car-jacking.
Kolasinac, however, has long since returned to the squad but Ozil has appeared and then disappeared, sometimes because of fitness, sometimes because Emery has felt other players have been more deserving of a chance.
Arsenal? Emery? Ozil? Who is to blame?
Former Aston Villa midfielder Lee Hendrie believes this is a situation Arsenal could and should have handled better.
"It's definitely mismanagement," he told BBC Radio 5 live.
"This is the problem these days in football, these bumper contracts players are getting and when they're not performing, it's coming straight to the headlines of how much money he earns and what he does.
"Whether Mesut Ozil is going to turn a corner - and I don't think he is - it just seems like there is a massive issue behind the scenes as to why he's not playing.
"On his day he's a world-class player but when you're earning that type of money, then you are going to come under scrutiny for earning that money and not playing.
Sutton, however, believes only Ozil himself can truly resolve the issue.
He said: "I don't care how much Mesut Ozil is paid, the main thing is how he's is performing on the pitch in an Arsenal shirt - and he's not.
"We aren't party to how Arsenal train or what's goes on but if Ozil was doing that well - and we know what a superb talent he is - Unai Emery would know what impact he would have on the team, so he would play him, because he wants to win games and improve.
"There must be something amiss and it looks Ozil will have to sort this situation out himself.
"Arsenal have either got to ship him out and just bite the bullet, or they've got to get him back playing in the side, but it's been down to their own doing and I feel they've caused their own problems."
Do Arsenal miss him?
The statistics would suggest so.
Since Ozil made his debut for the Gunners, no player has created more chances than him. In fact, no-one comes even close.
|Premier League (since Ozil's debut)|
He has also been the club's top assist maker in three of their last six seasons, although admittedly did not feature in the top three of the list in the last campaign.
|Premier League (since Ozil's debut)|
Against Sheffield United, the influence of the midfield five of Nicolas Pepe, Granit Xhaka, Joe Willock, Matteo Guendouzi and Bukayo Saka paled in comparison to the Blades.
They managed two key passes between them compared to five for the Sheffield United midfield.
What does Ozil say?
Ozil has been quiet on the matter for a long time, but recently provided some insight into the situation he finds himself in.
Speaking to The Athletic, he said: "When I signed the new deal (in 2018) I thought about it very carefully.
"I didn't want to stay for just one or two more years, I wanted to commit and the club wanted me to do the same.
"You can go through difficult times, like this, but that is no reason to run away and I'm not going to. I'm here until at least 2021.
"Whenever people see me in the street I always say, 'This is my home'. I'm going nowhere."