Gnabry joined Arsenal's academy from Stuttgart in 2011, when he was just 16.
He was at London Colney for five years, during which time he struggled to break through and ended up on loan at West Brom.
It was there that Tony Pulis infamously refused to play Gnabry, citing that he was "not ready".
Gnabry returned to the Gunners in February 2016, but he only featured once for them in the Premier League before the season was out. In total, he made 18 appearances for the north Londoners and scored once.
Eventually, Gnabry was sold to Werder Bremen that summer for a negligible fee - much to the confusion of many Gunners who highly rated the youngster.
However, former manager Arsene Wenger claims there were underhand tactics employed by Bayern Munich which pushed Gnabry out of the door.
Gnabry ended up signing at Bayern a year later, for only a slightly higher fee than he'd joined Bremen for.
It was reported that there may have been a verbal agreement in place between Gnabry, Bremen and Bayern when he left Arsenal which would allow him to join the giants in 2017.
Now Wenger claims that he thinks such an arrangement was in place.
"We tried to extend his contract for a very long time and I think that Bayern manipulated behind the scenes, that if he went to Bremen he would join Bayern after," he told beIN Sports.
"He was always a very talented boy who lacked confidence in some stages, but we always thought we had a player who could achieve a lot.
"He came back from a very bad experience at West Brom where his confidence was destroyed. I tried to rebuild him because I believed in him."
The 24-year-old German recently scored four goals against Tottenham in a memorable 7-2 Champions League victory.
He followed that up with another strike for Germany in their 2-2 friendly draw with Argentina on Wednesday night – and Wenger has challenged his former player to keep it up.
"A top-level career is consistency," he said.
"If you look at the players that dominate our sport it’s the ones who show huge consistency and that’s what is it at stake.
"Can he maintain the quality of performances that he showed the other night?"
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