Arsenal manager Mikel Arteta said Kai Havertz was injured and claimed he "destroyed all the indicators we have in the gym over the past decade", but he made a "in-body transformation."

Havertz has ripped his hamstrings during a warm weather training break in Dubai since February but can play against Newcastle United in Sunday's Premier League home game.

It was not initially clear whether Havertz will reappear this season, but his pace of recovery impressed the club staff, and some fans suggested he look more muscular during his opening ceremony training at the UAE Stadium on Wednesday.

"There's a transformation in his body," Arteta said. "The last three years of his career have been so solidified that he didn't have time to do it, and it's a window that he really wanted to use it.

“To be fair, the staff and how they explain the opportunity for him to have different levels of physicality and things he can improve can even help him become a player psychologically and more efficiently.

“He joined that, he worked hard, and you could see his presence and I think he destroyed all the metrics we have in the gym over the past decade.

“Strength, acceleration, muscle mass, the way he increases certain abilities in his body, agility, and he is incredible.

“It was an excellent effort for everyone in this case. The last home game was always a special moment and it was our chance to end the Champions League qualification.

“For someone who doesn’t have that mentality on the team, the only thing he does is raise the bar in the building because the others in the injured building are looking at him, ‘If I don’t do that, I’ll look bad, so it’s part of the culture.

"And it's very grateful because when a player who is not playing is doing it, it just raises the bar for the next player. If he's not on that level, he's going to be exposed so that it can make us better."

Arsenal hopes to tell ESPN this summer that Benjamin Sesko of RB Leipzig, Viktor Gyökeres of Lisbon and Alexander Isak of Newcastle are considering – with sources this summer, Havertz's role on the team.

Havertz remains Arsenal's top scorer in the league, with his name nine, Arteta said: "One of Kai's greatest qualities is his versatility and his target threat, he's smart as long as he plays him, and he'll be in the No. 9 game, he'll be a midfielder in the offense and he'll be very important for our team."