When Arsenal's team sheet arrived on Thursday evening, one enforced absentee stood out.
Kai Havertz was missing due to suspension. He played in all 26 of the Gunners' league games this season and was the only player to do so.
At the final whistle of the 2-0 defeat to West Ham, there was a longing for the guile and physicality of a man who was once roundly criticized for those parts of his game. How times have changed.
This week marks six months since Havertz joined from Chelsea for £65 million. He returns to the Arsenal squad this afternoon when they visit Fulham.
It has been a remarkable transformation after overcoming a crippling battle with confidence, groans from his own supporters and positional confusion to become an integral piece of Mikel Arteta's puzzle.
Kai Havertz completed an expensive move from Chelsea to Arsenal in London last summer
Mikel Arteta saw his side lose ground in the title race after a stunning 2-0 home defeat to West Ham
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Following the club's Community Shield victory over Manchester City in August, it is understood the midfielder did not take part in Arsenal's post-match social media video. Partly due to shyness, partly due to the feeling that he had not yet been able to settle down.
For Havertz, his transfer was strengthened as he came from a local rival. The Gunners faithful demanded he hit the ground running. The costs didn't help either. A fee of £65m is no small change, while £105m Declan Rice is playing as if he has been at the club all his life since signing just a few weeks later.
It all started during the Washington DC leg of the pre-season tour in July during Havertz's first Gunners appearance in the MLS All-Star Skills cross-and-volley challenge.
As the 14 deliveries came into the area one after another, the 24-year-old sprayed them everywhere but on target.
You sensed after the first few misses that he would rather let the ground swallow him up than accept the challenge.
His first competitive games were marked by a sense of unease on the ball and confusion about his role. Arteta had earmarked him for a left-sided midfield position alongside Rice and Martin Odegaard. At first, Havertz didn't know what positions he should take and when he should be there.
That lack of confidence was on display against Manchester United in September when he gave the ball away to Christian Eriksen, who set up Marcus Rashford for United's opener. The fans' groans were heard all over the Emirates and after that mishap he avoided receiving the ball, quickly releasing it backwards or to the side.
Now he is a completely different man, scoring three goals in his last six league games. Insiders say the 1-0 defeat at Newcastle was the turning point, especially his foul on Sean Longstaff.
Insiders say the 1-0 defeat at Newcastle was the turning point for Havertz, especially his foul on Sean Longstaff – for which he was booked (pictured)
It was not that the club wanted the German to aggressively eliminate his opponent. But his desire to fight for his team in a hostile atmosphere showed Arteta and those in charge that he has the character the team needs.
“He is not someone who wants to be on the front line, or at least he doesn't show it that way, but then if you ask him to go to war he will be the first,” Arteta said.
Sources say Arteta wanted Havertz so badly because he felt how little confidence the player had at Chelsea and knew he could improve him.
Furthermore, the club hierarchy saw his potential to play in two positions at once – a skill that not many players can perform effectively.
His physical presence could make him a target to play in the man-to-man press often used by opponents this season. This was sorely missed against the Hammers. In the final third he counter-presses aggressively and penetrates the gaps due to his natural instincts as an attacker. He also makes a shift defensively, mainly as an aerial foil for opponent crosses and kicks.
That versatility is reflected in his heat maps. Against Liverpool, Havertz can be seen making deep runs down the left flank, while also moving back into his own defensive area.
Against Brighton he crossed the penalty area for aerial attacks and worked cleverly with the pockets on the edge. That helped create space for the likes of Gabriel Jesus to get into shooting positions. It is clear that the club were surprised by the criticism Havertz received early on and did their utmost to make him feel comfortable.
That concern was on display after his late winner against Brentford, when Arteta headed for the 6ft 11in star at full-time and pushed him towards the away fans for cheers.
The German has already made a habit of scoring decisive goals for the Gunners this season
As a person he is a shy, thoughtful character and well-liked by the club, which is why his recent form has been so well received by teammates.
Off the field he is passionate about animals. He has three dogs and a horse, sponsors a donkey sanctuary and his charitable foundation, the Kai Havertz-Stiftung, focuses on animal protection. The club's training ground, Labrador Win, has even visited the Havertz household.
If the Gunners can reverse their recent slump, the club's dog won't be the only prize Havertz gets his hands on.