Oscar winner denies Bolton in battle at the Bridge
Premier League leaders Chelsea made hard work of Bolton but they advance to the Capital One Cup fourth round thanks to Oscar's second-half strike in a 2-1 win at Stamford Bridge.
Goalkeeper Petr Cech was captain, starting for the first time this season after being displaced as first choice by Thibaut Courtois, but his services were barely required as the Blues dominated.
Andre Schurrle spurned a host of chances and Bolton goalkeeper Andrew Lonergan was in fine form to deny the hosts.
French defender Kurt Zouma, on his debut, struck from a corner after 25 minutes to break the deadlock but the anticipated flood of goals did not materialise.
Chelsea's profligacy was punished and their defensive frailties exposed when Bolton captain Matt Mills headed in an equaliser six minutes later with their only real opportunity.
It denied Cech a clean sheet and leaves the normally miserly Blues with one shutout in seven matches this season.
Oscar saved his side's blushes by striking from 25 yards out after 55 minutes for what proved to be the winner in a contest which should have been far more comfortable for Jose Mourinho's men.
Still Didier Drogba, who came on as a substitute 18 minutes from time, must wait for the first goal of his second spell.
Drogba netted 157 goals in 341 appearances in his eight-year first spell, including during the Champions League final win in Munich in 2012.
The Ivory Coast striker did not have an opportunity of note on a night when Chelsea were left to ponder how fearsome their strikeforce is without Diego Costa, whose hamstring problem currently limits him to one game a week.
Drogba's most telling contribution was in his own box, clearing a Bolton corner in the final moments.
Elsewhere, Brighton breezed into the fourth round with a 3-0 victory that ended Burton's giant-killing run.
Goals from Rohan Ince, Kazenga Lua Lua and Craig Mackail-Smith justified Seagulls boss Sami Hyypia's decision to make nine changes to his side.
CAPITAL ONE CUP 4th ROUND DRAW
Tottenham v Brighton, Stoke v Southampton, Bournemouth v West Brom, Shrewsbury v Chelsea, Liverpool v Swansea, MK Dons v Sheffield Utd, Manchester City v Crystal Palace/Newcastle, Fulham v Derby.