He announced himself to the world by scoring a 90th-minute free-kick from 45 yards against Borussia Dortmund back in 2014, but beyond the special one-off moments, the Bundesliga has had the privilege of witnessing Hakan Calhanoglu’s evolution from rough-cut prodigy to reliable first-team regular for club and country. Now on his way to AC Milan, the Italian side are getting a very special player indeed.

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The potential possessed by the Mannheim native was clear to see when he took to Germany’s top flight with relative ease as a 19-year-old, making his Bundesliga debut in a 3-3 draw with Schalke. Now, having been moulded by the highs and lows of a professional career, from battling relegation with HSV to scrapping for a top-four finish with Bayer Leverkusen, Calhanoglu has blossomed into an experienced, highly-talented product of the German football system.

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Karlsruher were the first side to sniff out his ability and, having broken into the first-team equation at the age of 17, Calhanoglu featured in 13 of his side’s 14 games after the winter break during the 2011/12 Bundesliga 2 season. KSC failed to beat the drop come the end of the campaign, but the playmaker’s talents had not gone unnoticed.

As a result, Hamburg snapped him up in 2012, before deciding that his development would be better served if he spent a further season on loan in Karlsruhe. They were not wrong. Still a teenager at the time, Calhanoglu went on to have a hand in 29 goals - 17 goals and 12 assists - in 36 appearances as KSC topped the table in the third tier of German football, convincing HSV that he was ready to make the step up.

Calhanoglu may have only spent a single season in the Port City, but it was in Hamburg where he truly matured as a player capable of making his mark at the highest level. His stunning strike in the 3-0 win over BVB was the highlight of his debut Bundesliga season, but far more impressive was his ability, as one of the youngest players in the squad, to shoulder responsibility and help carry the Bundesliga’s only ever-present side to safety via the relegation play-off.

The ability to step up to the mark at crucial moments demonstrates a level of mental fortitude that cannot be taught. With a competency and understanding of the game belying his years, Calhanoglu’s talents were on display for all to see in his debut Bundesliga season.

The rising star chipped in with 11 goals and four assists, a tally made all the more impressive when you consider that four of his goals came against top-six sides - Bayern, Dortmund, Leverkusen and Wolfsburg - and a further four were scored during relegation six-pointers, in which HSV picked up seven of a possible nine points.

However, the strain of expectation as part of a relegation-threatened Hamburg side proved unappealing and Calhanoglu promptly sought pastures new. “I came here with great hope, but I have since lost that,” Calhanoglu told SportBild back in 2014, just 105 days after signing a contract extension with the club. “I don’t want Hamburg to build a wall around my career. I want to reach the levels of Cristiano Ronaldo or Lionel Messi. I want to be a player that everyone is talking about.”

Watch: Calhanoglu's Top 3 free-kicks

Even at the tender age of 20, Calhanoglu ticked plenty of boxes scouts look for in an advanced, creative playmaker. Beyond his obvious penchant for set-piece situations, the 26-time Turkey international boasts, vision, technique and a knack for reading the game two or three passes ahead of play - all of which were qualities that Leverkusen looked to tap into when they signed the midfield maestro.

A strong first season with Die Werkself saw Calhanoglu make his international debut for Turkey, steal the attention of neutrals on the UEFA Champions League stage and help Bayer 04 to a top-four finish. However, the 2015/16 campaign was not as smooth a ride. Leverkusen finished the season in third, but Calhanoglu’s performances were not up to his normal standards, a fact the No10 personally addressed.

“I can play a lot better,” admitted Calhanoglu in an interview with Express during pre-season. “I want to get back to the level of performance that I was demonstrating during my first season with the club. The competition for places in my position has gotten stronger so there needs to be more coming from me - I know that.”

The Turkey international proved to be a man of his word as he had a hand in 11 goals in 15 Bundesliga appearances before a four-month ban from the Court of Arbitration for Sport (CAS) stopped him in his tracks. Calhanoglu admirably decided to forgo his wages during that time, but his absence proved pivotal as Leverkusen ended up battling the drop as opposed to competing for European qualification.

Looking at the bigger picture though, Calhanoglu's development stands as a prime example of not only how proficient German football can be in producing young talents, but also how carefully they are nurtured into stars fulfilling their true potential.

James Thorogood

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