Tuesday's 0-3 defeat to Brighton was the final straw for Chelsea's sporting fortunes. It was the London club's fifth straight league defeat - a run in which Chelsea had failed to even score a goal.
The loss leaves Chelsea in seventh place in the Premier League table, seven points behind fifth-placed Liverpool, who currently hold the final Champions League spot.
Rosenior took over as Chelsea manager on January 6th on a six-and-a-half-year contract. Now, three and a half months later, his time in the post is over.
Calum McFarlane will temporarily take over the job while Chelsea wait for a new coach, reports The Guardian.