Branislav Ivanovic has admitted Chelsea need to work harder at the back if they are to be successful and keep their UEFA Champions League dream alive.
The Blues have earned plenty of plaudits for transforming the way they play this season but their new-found attacking verve has so far garnered them only four points from their opening three Group E games.
Manager Roberto Di Matteo looks unlikely to abandon the approach in Wednesday night's crunch clash with Shakhtar Donetsk, insisting Chelsea's philosophy was "changing".
But Ivanovic does not believe that can be at the expense of the Chelsea defence that proved so inspirational in Europe last season.
"If we're going to be successful, we have to be defensively strong as a team," he said.
"This is the part of the game we have to improve as a team. I'm sure we can create chances against any team, and can score the goals. The question is about our defence and that's what we're going to work harder on.
"The importance is to be solid and compact, in the group stage especially.
"If we do that, we'll be successful because, for sure, we'll still create the chances."