A close ally of owner Roman Abramovich over the seasons, Emenalo was initially appointed as chief scout in 2007, before moving into the role of technical director four years later after a brief spell as first-team coach during Carlo Ancelotti's spell as manager.
Mounting internal tensions at Chelsea have been the subject of much speculation since the end of last season, fuelled by apparent difficulties and disagreements in the transfer market.
The club confirmed reports from the Daily Telegraph, Emenalo's decision to step down comes in the form of his wish to back away from a potential 'three-way power battle' at the top of the club alongside manager Antonio Conte and chief negotiator Marina Granovskaia.
The report notes that Conte and Granovskaia have had their differences. It has long been thought that Conte had frustrations with Emenalo and his handling of transfers, but the Telegraph suggests that the Nigerian retired defender has been a big supporter of Conte.
Therefore rather than a victory for Conte, it is more likely to be seen as a blow to Abramovich, with Emenalo said to be one of the few individuals trusted to give advice by the billionaire owner.
Despite scepticism of what Emenalo has contributed at Chelsea, the club has enjoyed incredible success during his association, including two Premier League titles, the Champions League, Europa League, a League Cup and three FA Cups.
In his role as chief scout and technical director, he has personally been responsible for the arrivals of numerous important players, such as Eden Hazard, Thibaut Courtois and Cesar Azpilicueta. Earlier, Belgian pair Kevin de Bruyne and Romelu Lukaku were also signings of his.