Chelsea’s head coach Liam Rosenior (AP Photo)

Chelsea FC have sacked head coach Liam Rosenior less than four months into his tenure, bringing a swift and dramatic end to a spell marred by historic underachievement.The decision came in the wake of a 3-0 defeat to Brighton & Hove Albion — a result Rosenior himself branded “unacceptable” — and a dire run that has seen Chelsea lose five consecutive Premier League matches without scoring. It marks the club’s worst such streak since 1912, underlining the scale of the collapse.“Chelsea Football Club has today parted company with Head Coach Liam Rosenior,” the club said in a statement, admitting performances had “fallen below the necessary standards” despite the season still being alive.Historic slump triggers ruthless callRosenior, 41, had arrived in January from RC Strasbourg Alsace following the exit of Enzo Maresca. While his appointment raised eyebrows, early promise quickly gave way to a staggering downturn.Chelsea have now lost seven of their last eight matches in all competitions, including a heavy Champions League exit to Paris Saint-Germain and a League Cup elimination at the hands of Arsenal FC.The Blues currently sit seventh in the table, seven points off the Champions League places with just four games remaining — far from expectations for a squad assembled at enormous cost.Financial strain, dressing room cracksAssistant coach Calum McFarlane has been placed in interim charge, beginning with a crucial FA Cup semi-final clash against Leeds United. His immediate task will be to salvage European qualification and ease the financial burden after Chelsea reported a staggering £262.4 million pre-tax loss last season.Behind the scenes, tensions had been brewing. Questions over the earlier sacking of Maresca were publicly raised by senior players including Enzo Fernández and Marc Cucurella, while inconsistent performances further strained relations between the squad and Rosenior.The club’s ownership group, led by Todd Boehly, has now dismissed five permanent managers in under five seasons, raising serious concerns about long-term stability despite over £1 billion spent on players.Chelsea confirmed they will begin a “process of self-reflection” to appoint a long-term successor, with names like Andoni Iraola, Marco Silva and Edin Terzic already linked.