Didier Drogba says Chelsea are "not ready" for the new season and must improve to get their Premier League title defence off to a good start.
Last season's Double winners were beaten 3-1 by Manchester United in the Community Shield at Wembley, a fourth consecutive loss in their warm-up schedule.
Carlo Ancelotti insists there is no major cause for concern as Chelsea build towards the visit of newly-promoted West Brom to Stamford Bridge this weekend.
However, with so many of the senior squad having been away on extended breaks after the World Cup and the likes of Michael Essien and John Obi Mikel coming back from long-term injuries, Drogba admits there is still some hard work ahead.
"The game against United showed we are not ready. We have to step up our game if we want to start the season well like we did last year," he said.
"A lot of players have only trained for 10 days. It is too short to be fit and ready for the big competition.
"We have to improve our game, even if we are not fit, and hope that in two to three weeks time we will be better.
"I hope it does not take that long but when you come back after a short holiday it takes a minimum of two to three weeks to have good preparation and be fit physically. I know I'm not ready yet."
Drogba added: "Against United, we played without intensity, but we are working very hard in training trying to get fit early.
"It is not going to be easy but we need more time."
Chelsea are understood to be close to completing the £22million signing of Benfica's Brazil midfielder Ramires, but so far Yossi Benayoun is the only senior player the Blues have added to their squad this summer.
Drogba, though, insists there is already enough strength in depth for the Blues to mount another sustained assault on both domestic and European honours next season.
"The squad is the same as last year and the quality is still there," said the striker, who netted 29 goals last season.
"If there are more players coming then that will be good for us because it will improve the level of the team, but if not then we know that we will have the quality to go very far in all competitions."
Goalkeeper Petr Cech is expected to be fit from his calf injury in time to face West Brom, but Ancelotti could yet consider bringing in more back-up, with Stoke's Asmir Begovic said to be on the Italian's radar.
Chelsea officials, meanwhile, maintain there was no deliberate snub by full-back Ashley Cole towards England manager Fabio Capello after the defeat to United at Wembley.
The club stress Cole simply stumbled as he climbed the steps towards the royal box and did not see the Italian.
Along with Chelsea captain John Terry, Cole was present for the initial group meeting with Capello and the rest of the England squad ahead of the midweek friendly against Hungary before heading off for warm-down sessions at Arsenal's Hertfordshire training base.
