Only 24,973 supporters turned up to watch the match against the Norwegians and they made their feelings known at the final whistle by giving Mourinho and his men a chorus of dissent.

Rosenborg, expected to be Group B's whipping boys, stunned Chelsea by taking a 24th-minute lead though Miika Koppinen but Andriy Shevchenko equalised for Chelsea in the 53rd minute.

But despite peppering the Rosenborg goal with more than 25 shots, hitting the woodwork on two occasions, Chelsea failed to find a winner.

"I have some sympathy with the fans. We have to be beating teams at home, whoever it is. You understand their frustration," said Cole, whose side play Manchester United in the Premier League at the weekend.

"We are getting chances but maybe not taking them or passing at the right times, so the jeering is fair enough.

"We should kill off teams and win these kind of games. Maybe there is a lack of confidence from a few players.

"We have only scored first in the Premier League against Portsmouth this season and we are disappointed at how that is going.

"We are conceding silly goals from free-kicks a lot which, for a team like us with the players we have got, we shouldn't be doing.

"Jose Mourinho did not say anything to us as the end of the game but we all know that he was got to be disappointed.

"We are disappointed with how it went and on Sunday we have to change that."

The Blues are suffering from the absence of both England midfielder Frank Lampard and striker Didier Drogba.

They contributed more than 50 goals between them last season but both are missing through injury and are not expected to be back for Sunday's vital clash with Manchester United at Old Trafford.

Drogba is still struggling with a knee injury while Lampard's recovery from a thigh strain is taking much longer to heal than anticipated.

But Cole insists Chelsea have the necessary quality within the squad to compensate for their loss and maintains Sunday's match against United would be the perfect time to kick-start their miserable season.

Cole added: "It is a huge game and maybe the Rosenborg result could help us - you have to be 100% going there (Old Trafford).

"We have to draw a line under things. We are disappointed in how it went against Rosenborg but Sunday is totally different. It can kick-start our season.

"It is not just the points but pride and the fight for the championship is on as well. We are fifth and that is not where we want to be.

"We have the potential to get results without Frank and Didier. It is not going too well but we are going to have to start winning games without them."

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