Antonio Conte warned his Chelsea team they must improve defensively after they edged past Bristol Rovers in the EFL Cup.
The squeaked into the hat for the third round following a 3-2 victory over the League One side at Stamford Bridge on Tuesday night.
Michy Batshuayi marked his first start with a brace and Victor Moses got on the scoresheet as the home side held a healthy 3-1 advantage at the interval.
Bristol Rovers came roaring back in the second half, pulling another one back shortly after the restart, and were unfortunate not to at least force extra time.
A simple goal from a set-piece and some sloppy defending which saw Chelsea concede a penalty left head coach Conte fully aware of the problems he faces at the back.
He said: “I knew this game would be very tough. I knew the atmosphere around this cup.
“I don't like it when we concede two goals with a free kick and a penalty. When you have the opportunity to kill the game, you must kill it.
“We must improve (our defensive work from set-pieces). We must see the danger. In England it can be a good chance to concede a goal.”
John Terry was left on the bench as youngster Ola Aina was handed his debut at right-back against Rovers.
It was heartening for Blues supporters to see the defender make his bow but the absence of Terry was sorely felt and highlights the need for reinforcements.
The transfer window slams shut next week and Conte has already admitted he is keen to bolster the Blues ranks before the deadline on August 31.
However, prime target Kalidou Koulibaly seems to be slipping away and means keeping Terry fit and welcoming back Kurt Zouma from injury is more important than ever.
England manager Sam Allardyce has left the door open for Terry to come out of Three Lions retirement and would put added strain on the veteran if the comeback did materialise.
Conte, a former international manager himself with Italy, refused to discuss his captain’s international status in the public domain in his post-match press conference.