Leon Goretzka's former team-mates have marvelled at the Bayern Munich star's physical transformation in recent years, particularly the muscle mass he has built without sacrificing speed or agility.
Goretzka has become one of Bayern's key figures, starting and providing an assist in his side's 8-2 demolition of Barcelona in the Champions League quarter-final last week.
The 25-year-old's development as a player has included a physical aspect, with the midfielder bulking up after joining Bayern in 2018 from Schalke.
Speaking to Goal , former Schalke defender Roman Neustadter has revealed that he is impressed with the physical development of his old team-mate.
"After I've seen his development, I wrote to him directly to send me the exercises he was doing!" Neustadter said. "Even at Schalke we saw that he has the physical abilities to build muscle mass without harming his game.
"Of course, he made the best possible use of the coronavirus break. You can't just decide for yourself: 'So, I'm gaining a few pounds of muscle mass'.
"I tried that myself when I thought I needed more muscles. However, I could hardly move afterwards! Leon's muscle growth was certainly precisely coordinated with the club."
Another former team-mate, Jan Kirchhoff, echoed Neustadter's sentiments about Goretzka maintaining his same level as a footballer despite gaining muscle mass.
"Although he is quite tall, he is very fast. Leon is a born box-to-box player and can cover unbelievably long distances in a very short time," Kirchhoff told Goal .
"That has always been his strength. He is energetic one-on-one and records a lot of ball recoveries. In the meantime, he gained a few pounds, but has not lost speed and agility. The fact that he has again improved athletically has certainly helped him. He now has the perfect mix."
Kirchhoff recalled a conversation he had with Goretzka earlier in his career when the midfielder told him that of any club in Europe, Bayern was the one he wanted most to join.
"I can still remember a conversation with him," Kirchhoff said. "Because he was such a great talent, I asked him which club he would like to play for one day: Real Madrid, Barcelona, Chelsea?
"He already said back then he would like to play for Bayern Munich one day, if he could choose the club. That was his clear goal, he achieved it and I'm very happy about that."