The beginning of the end for Jackson was a red card at Newcastle which almost cost his side a top-five place in the Premier League and Champions League football.
His elbow into the face of Magpies defender Sven Botman was rash and ill-disciplined.
But another red card followed for a high foot against Flamengo at the Club World Cup, which meant he was banned from two competitions simultaneously.
Multiple sources with knowledge of the Chelsea squad reveal how Enzo Maresca started to treat Jackson differently and began to lose trust with the forward – a view shared by some in the hierarchy.
That is despite Maresca saying in April that Jackson was his “perfect number nine” and he wanted “a copy of Nico”.
Many inside the club and close to the player believe the striker’s move to the Blues has been a success.
They highlight the fact Chelsea paid just £32m to sign him from Villarreal and how six years ago he was playing on sandy pitches in Africa without elite-level European coaching available to him.
However, such a rapid rise meant he was often harshly perceived as the weak link by fans and pundits alike.
The pressure appeared to get to him after criticism from former midfielder John Obi Mikel, who he argued with on social media.
But Jackson also outscored Chelsea legend Didier Drogba in his first season – netting 14 goals to the Ivorian’s 10. He then scored 21 goals in his first 50 games to equal one of Africa’s great strikers at Stamford Bridge.
In truth, Jackson was a better overall footballer than finisher in front of goal. His importance was often linked to Chelsea’s lack of alternative options during his two-year spell at the club.
His loan fee upon joining Bayern is among the biggest ever, ranking behind just Giovani Lo Celso’s fee when he joined Betis to Tottenham and two different Alvaro Morata moves.
It shows how Jackson polished his skills while at Chelsea – with the Blues delighted to potentially double their money from their initial outlay.
Watch all your favorite Amazon Prime Video Sports broadcasts live and free. Get access to NFL, NBA, NASCAR, WNBA, and more – all included with your Prime membership!