Luiz Felipe Scolari is at a loss to explain Chelsea's dismal home form and fears that if it does not improve they can forget about winning the English Premier League title.
The Blues have claimed victory in just three of their nine home league games this season, while winning all eight of their matches on the road.
Chelsea manager Scolari is mystified as to why his side are finding it so hard to conquer opponents at Stamford Bridge, where they have won just two of their last seven games.
"It's difficult to explain what's happened. I am frustrated," the Blues boss said. "It's important for us to win at home but now we're playing better away than at home and I need to change this idea.
"We need to win two or three games here and after this, maybe we'll play the same as in the last five or 10 years," added Scolari, who in October saw Chelsea surrender their 86-match unbeaten home league record with a 1-0 loss to current table-toppers Liverpool.
"But now all the teams come to Stamford Bridge and play back with 10 players within 40 metres. There is no space for my players and sometimes my players need to improve and dribble, try something different.
"At this time, it's difficult for us," Scolari said. "Sometimes we don't have the quality to beat the other club and we need to accept that."
Chelsea blew their chance to overtake Liverpool at the top of the table here on Sunday.
The Blues drew 1-1 at Stamford Bridge with West Ham, managed by Chelsea legend Gianfranco Zola, in a fiercely-contested London derby.
Wales striker Craig Bellamy gave the visitors a 33rd-minute lead with a well-taken strike but France forward Nicolas Anelka rescued a point for Chelsea six minutes after half-time with his 100th Premier League goal.
The result left Chelsea in second place, one point behind Liverpool, while West Ham are 16th in the table, a point above the relegation zone.
"If we draw or lose but play well I am not frustrated, but in the first-half we did not play well," Scolari said.
The 60-year-old former Portugal manager, who guided his native Brazil to victory in the 2002 World Cup, said Chelsea were passing the ball around the midfield but failing to create chances in front of goal.
"After our goal we tried to pressure and open the midfield and play with three strikers. But the strikers are in a line.
"I need to train them more and the players need to understand that three players can play in attack -- but not be fixed there. They need to come back and work without the ball."
Chelsea went into the Hammers match having beaten Romania's CFR Cluj 2-1 at Stamford Bridge on Tuesday to reach the last 16 of the Champions League.
Zola said he thought the strains of playing European football were taking their toll on England's "big four" clubs, who have all progressed from the Champions League group stage.
"When you play a Champions League match, it's very demanding, it drains you," the Sardinian said after a weekend where the 'big four' all drew in the Premier League.
"We took advantage of that but it won't be easy for anybody to come here and pick up points.
"I don't think it's only at Chelsea. It seems to me that also Liverpool, Manchester United and Arsenal are all dropping points and they are all teams that are playing in the Champions League.
"Also the small teams are getting more organised, they are playing more tactically and making it more difficult for the big teams to beat them."
Zola scored 80 goals in 312 games between 1996 and 2003 for Chelsea, winning the European Cup Winners' Cup, the European Super Cup, two FA Cups and a League Cup in the process.
The former Italy striker, on his return to Stamford Bridge, was given a hero's welcome by the home crowd.
He said Sunday's draw would help boost morale at Upton Park in the Hammers' bid to pull away from the relegation zone.
"This performance will help build up our confidence again," he said.
"Maybe this time when we play at home we're going to have a litle bit more confidence, more freedom, and less pressure."