Costa notched his third goal in as many league games as he powered home Cesc Fabregas’ through-ball after just 35 seconds on Merseyside.
Defender Branislav Ivanovic then made it 2-0 less than two minutes later when he peeled away from the defence and slotted past Tim Howard, despite replays suggesting he may just have been offside.
The Blues look set to be heading back to the top of the Premier League after Manchester City’s shock loss to Stoke City.
Chelsea’s stunning start prompted a quick flurry of updates on Twitter, and here are some of our favourites.
Former Derby defender Jordan Stewart (@jordanstewart3) is impressed by the opener: “Let’s go @chelseafc powwwww!”
Manchester United legend Paul McGrath (@Paulmcgrath5) keeps it short and sweet: “Costa is king !”
Hull City midfielder Ahmed Elmohamady (@Elmo_27) feels Fabregas deserves credit for the assist: “Wooooow cesc, what a pass”
Ex-Everton striker Gary Lineker (@GaryLineker) pokes fun at some recent media reports: “Diego Costa, who is out injured for a few weeks, has given Chelsea the lead in the first minute.”
Lord Sugar (@Lord_Sugar) is impressed: “Chelsea on fire – 2-0 up after 3 mins”
Lineker @GaryLineker) can’t keep up: “Chelsea are scoring quicker than the time it takes to tweet. 2-0!”
McGrath (@Paulmcgrath5) reckons it’s all over already: “Blow for full time ref ! Chelsea wow !”
But ex-United star Alan Tonge (@Alan_Tonge) is not impressed by a certain official’s performance: “Is the linesman filming an advertisement for specsavers on this side?”
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