When Douglas Costa signed for Bayern Munich in the summer of 2015, the German champions thought they were acquiring one of the world's best attackers, and someone who would eventually fill the huge shoes of trusted wingers Franck Ribery and Arjen Robben.

Yet when Bayern reached the business end of last season, coach Carlo Ancelotti reverted to the default pairing of Ribery and Robben - a blow for the 26-year-old who was considered the future of the club in Pep Guardiola's final season. However, the decision to drop him was not undeserving given how Costa's form has tailed off over the past year.

Costa is a brilliantly talented footballer. With one explosive swing of his left foot, he can unleash untold damage on opponents. Just ask Rostov, Darmstadt or Arsenal. But Costa's moments of brilliance became ever fewer and farther between as his Bayern career got closer and closer to its inevitable conclusion. Consistency is the very least expected at Bayern and Costa has failed to produce on a regular basis under Ancelotti.

His attitude has also been questioned, with some fans and the club's hierarchy doubting whether he identifies with the club and all it represents. Costa's reluctance to buy into the Bayern way of life has left him on the brink of a move to Juventus, who have offered a reported 40 million euros ($44.5 million) after seeing an initial offer rejected. The Bianconeri's sporting director, Giuseppe Morotta, has confirmed that the deal is close to being completed and that the player will be wearing black and white - not red - next season.

"We received permission from Bayern Munich to meet with the player and his advisors. Costa is willing to join us next season," he said.

'What could have been'

The only stumbling block appears to be Costa's salary in Italy, with the player reportedly believed to be demanding over nine million euros a year, more than World Cup winner Sami Khedira or long-serving goalkeeper Gianluigi Buffon earn. With deals having been thrashed out between the clubs recently for Arturo Vidal and Kingsley Coman, there is hope agreement will be reached in the coming days. Bayern CEO Karl-Heinz Rummenigge general has good relationships with Italian clubs given his grasp of the language, having played for Inter Milan in the 1980s. This is another reason why Bayern have so successfully done business in Italy in recent years.

While Champions League finalists Juventus are hardly a step down in quality from Bayern, Costa's apparent lack of willingness to fight for his place at the Allianz Arena and become a key part of Bayern for years to come should be at least a little concerning to the Serie A club, who with Paulo Dybala, Mario Mandzukic and Juan Cuadrado among their attacking options, will not guarantee Costa a starting berth.

Costa's time at Bayern is a classic case of "what could have been" as the player departs having failed to enhance his reputation during his time in Germany. He joins the likes of Landon Donovan, Lukas Podolski and Xherdan Shaqiri, who have failed to fulfil their potential at Bayern. While the deal demonstrates good business by Bayern, Juventus are acquiring a player whose inconsistency overshadows his undeniable ability.