With barely a minute on the clock, goalkeeper Petr Cech suffered a fractured skull after a collision with Reading striker Stephen Hunt.
He was ruled out for three months and wore a protective head gear until his retirement from professional football at the end of last season.
The Czech shot stopper was replaced by Carlo Cudicini, who also suffered concussion later on in the game after he was bumped into by Reading defender, Ibrahima Sonko.
With all substitutions made, Chelsea manager, Jose Mourinho, put John Terry in goal as Chelsea battled to a priceless victory.
Frank Lampard’s deflected free kick on the stroke of half time proved to be the winner, but John Obi Mikel, on his first Premier League start for the Blues, was red carded for two bookable offences.
Cudicini’s injury meant Chelsea finished the game with nine men.
The two goalkeepers failed to recover in time, meaning Chelsea were left with no choice but to field third-choice goalkeeper, Henrique Hilario, in the following mid-week’s UEFA Champions League game against Barcelona. Chelsea won the game 1-0 thanks to a Didier Drogba wonder strike.
Cech, who holds the record for the goalkeeper with the most Premier League clean sheets (202), won 13 major honours during his time at Chelsea including four Premier League titles and the 2012 UEFA Champions League.
He has since begun a career in Ice Hockey, signing for English National Hockey League side, Guildford Phoenix.