Liverpool manager Jurgen Klopp has told Germany's Sky Sport News HD that he has always believed in Mario Gotze after the player was diagnosed with a medical issue which has affected his fitness and form.
Klopp added that Gotze's critics should apologise after the Borussia Dortmund attacking midfielder was ruled out for the rest of the season due to metabolic disturbances.
"Mario Gotze's health problems are a logical explanation for this and the problem that arose in the past few years," Klopp said. "I'm just happy that this has now been discovered.
"In the end, hopefully quite a few people will have to apologise. I would expect that because I am 100 percent convinced by the lad."
Klopp gave Gotze his debut at Dortmund in the 2010-11 season, when they lifted their first Bundesliga title in nine years. Gotze was then a key figure as they defended their title before joining Bayern Munich for €37 million in 2013.
His three years in Munich started well, and he scored the winning goal for Germany at the 2014 World Cup, but a series of injuries and a dip in form saw the 24-year-old's value drop and he returned to Dortmund last summer in a bid to relaunch his career.
After just a handful of appearances, his season was brought to an end in February by the diagnosis.
Klopp continues to be linked with a move to take the player to Liverpool.