Hertha Berlin defender John Brooks has told Bild he "can't thank Jurgen Klinsmann enough" for selecting him in the U.S. World Cup squad.
Brooks, 21, had been a mainstay for Hertha as they won promotion to the top flight in the 2012-13 campaign, but injuries and form problems limited his impact in the Bundesliga as he made just 16 appearances in total.
Towards the end of the season, Brooks was not called up to the Hertha squad because of "a large-scale back tattoo" which made football impossible for him, with coach Jos Luhukay saying at the time: "I don't have any understanding for that. The tattoo could lead to an inflammation, and, naturally, that is not good."
However Brooks went on to start all the remaining matches of the season, and was later called up for Klinsmann's World Cup squad, scoring a header to secure a 2-1 group stage win over Ghana in his only appearance in Brazil.
"I can't thank Jurgen Klinsmann enough for being called up," Brooks said on Friday. "I hope I was able to pay back that trust with my goal against Ghana.
"Klinsmann taught me that you have to give it your all in every training session, to bend over backwards and develop an unbelievable will. He is a super-motivator. I also know that from Hertha coach Jos Luhukay. Yes, I have changed and become more confident.
"I have taken home a lot of experiences from the World Cup, and it has made me more mature. I want to become more consistent -- not only play to well for 80 minutes, but to concentrate until the last minute."
Berlin-born Brooks may not have landed the ultimate prize in Brazil, but was presented with a medal along with the rest of the USMNT by U.S. vice-president Joe Biden after their 2-1 against Ghana.
"I often look at it," he added. "It reminds of the great time, makes me proud and it feels good."