In a crushing blow, the France international has been ruled out for six months after damaging his anterior cruciate ligament against Manchester United on Sunday.
Zouma will undergo surgery this week after falling awkwardly on his right knee, hyper-extending the joint in the process.
The youngster will miss the rest of the season, the European Championships – which are being played in his homeland – and is facing a fight to be ready for the start of next season.
In confirming the news, Zouma posted on his Twitter page: ’Scans today has shown I injured my ACL. I will have surgery this week & will come back stronger.
On Sunday night, despite leaving Stamford Bridge on crutches and in leg brace, Zouma was hopeful of playing again this season.
Indeed, talk behind the scenes was that the injury, despite how horrifying it looked on replays, wouldn’t end his campaign.
But any hope of Zouma playing again this season evaporated after scans flagged up the need for cruciate ligament repair.
The news will come as a huge disappointment to Zouma, who has nailed down a place in Guus Hiddink’s starting XI in recent weeks.
Likewise, Zouma’s long-term injury leaves the Blues short of recognised central defenders for the season run-in.
Gary Cahill, who was growing agitated at his lack of action in recent weeks, is almost certain to replace Zouma alongside John Terry in central defence until the end of season.
But Hiddink is short of options beyond Terry and Cahill following Zouma’s injury.
January signing Matt Miazga could be used as cover, likewise Branislav Ivanovic can also play as a makeshift central defender if required.
Centre-backs Andreas Christensen, Michael Hector, Papy Djilobodji, Tomas Kalas and Kenneth Omeruo have all been loaned out.
Zouma’s injury could impact on Terry’s future given the uncertainty at centre-back after Zouma was ruled out of the season.
The 35-year-old revealed the club’s decision not to offer him contract extension, meaning he will leave Stamford Bridge in the summer, earlier this month.
Chelsea insist they have not made a final decision on Terry’s future and could still offer him a 12 month deal, however, the former England captain has since claimed a breakdown in communication between both parties on the matter.
But with Zouma now set to miss the start of next season, and Cahill’s long-term future at the club far from clear, the issue of Terry’s future could yet take another twist.