Didier Drogba admits Chelsea have missed the experience of the players who left Stamford Bridge last summer during their recent miserable run.
The Blues sold or released proven internationals Michael Ballack, Ricardo Carvalho, Joe Cole, Deco and Juliano Belletti during the close season, promoting youngsters Josh McEachran, Jeffrey Bruma, Gael Kakuta and Daniel Sturridge. Injury and illness robbed them of Drogba, Frank Lampard, John Terry and Michael Essien for part of the season
Drogba told Sports Illustrated: "We've had a lot of injured players, and the team has changed from last year. We lost five great players in Ballack, Belletti, Deco, Carvalho and Joe Cole."
He added: "And we replaced them with young players like Bruma, Kakuta and McEachran. They are good players, but they need time to adapt."
Drogba has struggled to rediscover his own top form following a bout of malaria. The 32-year-old revealed he was laid low for two months with the illness.
"At first, the tests didn't show that it was malaria. The doctor thought it was flu, so that's why we lost time," he said.
"While we thought it was flu, I was playing, because for me I can handle flu. I lost fitness, but I was working hard and trying to help the team. For me to be playing now, it's already a good start because it was a difficult moment for me to have malaria - very difficult."
Drogba smashed in 37 goals for Chelsea last season but has managed just nine so far this term.
He said: "It's maybe not what I was expecting, but I've had malaria and surgery before the beginning of the season for my hernia to make sure I'll be okay for the next few years.
"I won't say I'm happy because we're having a difficult moment, but when you look at the amount of games I've played and the number of goals and assists I've had, I know it's not the best, but it's not bad. And I can continue to improve that. I'm not worried about my performance. If we win the league and I score only 10 goals, for me it's fine."