Midfielder Michael Ballack insists Chelsea's fighting spirit and power have returned under the leadership of interim coach Guus Hiddink, as they prepare to face Juventus in Turin tonight.
Phil Scolari was axed amid speculation he had lost the dressing-room and that fitness levels had dropped badly under his regime.
Germany captain Ballack was reluctant to discuss past events ahead of tonight’s Champions League last-16 tie against Juventus in Turin, but he did admit the team's famous fighting spirit had been re-discovered under the Dutchman.
"I don't want to speak too much about the past," said Ballack. "We had a lot of good games under Luiz Felipe Scolari as well but, in the end, we were struggling a little bit.
"We weren't having the success everyone expected so the club made a change. The players have to accept we have a new coach. It's always difficult to change a coach in the middle of the season, but we've come back to winning in the last five games, which is fantastic.
"He (Hiddink) has had great success in the past. He has a lot of experience and great charisma, and he's shown that in this short time with Chelsea.
"We are back to winning. Even in a few weeks, we came back to one of our biggest strengths which is the power, the fighting spirit of Chelsea. We can still play better, but we're on the way up. Everyone can see this and that's important."
Ballack added: "It's always about the responsibility and the key players taking on that responsibility. You have a hierarchy in a team, of course."
Ivorian striker Didier Drogba's first-half winner at Stamford Bridge has given Chelsea a vital advantage going into the return leg in the Stadio Olimpico.
Chelsea tired visibly in the second-half of the first leg and Ballack predicts tonight's game will be just as punishing.
"It was tight in the first leg and that is what we expect tonight as well," the German added. "We started well at Stamford Bridge and scored that early goal, but more important was the fact we didn't concede.
"We were very happy with the result, but we know we've got another tough 90 minutes ahead of us."