Chelsea 1 Rosenborg 1: Mourinho left with egg on his face after Chelsea held by Rosenborg

The pressure is on Chelsea, Jose Mourinho admitted last night, after his side failed dismally against Champions League minnows Rosenborg in an embarrassing 1-1 draw with the Norwegians. After his third successive game without a victory, the Chelsea manager lambasted his side for failing to convert their possession into goals.

Chelsea needed an equaliser from Andrei Shevchenko eight minutes after half-time to rescue them from potentially the most humbling defeat in their recent history after the Rosenborg defender Miika Koppinen scored in the first half. Another goal conceded from a set-piece was compounded by a sparse crowd of 24,973 and no progress, Mourinho said, in the rehabilitation of his injured senior players.

After defeat to Aston Villa on 2 September, the draw with Blackburn Rovers on Saturday and last night's result, Mourinho said that he was "very disappointed".

"The history of the game is simple," he added. "We had plenty of chances, and scored one goal. To score two, we maybe needed 40, to score three maybe 60 chances.

"In 90 minutes, you don't create 40 chances and 20 [his team had 29 shots on goal] weren't enough. That wasn't my strikers, it was my team. My team played against a side who played like the smaller teams do when they visit the better teams. They came to defend, organised, but we produced 20 chances. We could say anything, but the history of the game was we couldn't score more than one goal with 20 shots.

"Of course, I'm alarmed. I'm not happy. But, first of all, I cannot score goals. And secondly, I have no good news from the medical department. The news I want is that the players will be back for training, but that's not coming."

With Frank Lampard, Didier Drogba and Ricardo Carvalho still out – as well as the long-term injured Michael Ballack and Wayne Bridge – Mourinho will not be savouring Sunday's trip to Old Trafford. The Chelsea manager may yet spring a surprise by bringing one of those players back into his squad, but he sounded downcast last night at the prospect of even one of them making a recovery.

"I have to fight with these people [the players who are fit]," he said. "They're trying their best. In the last two matches, against Blackburn and Rosenborg, we did enough to win both matches. We have had no luck. But the reality is a 2-0 defeat to Aston Villa, 0-0 [against Blackburn] and 1-1. Nobody is happy.

"It's not a good result. But we're not scared. Schalke [also in Group B] lost at home to Valencia. Maybe it'll be more difficult at first. Maybe we'll need four points against Valencia. We've played three games and dominated, created chances, and we've scored one goal. That's the reality at this stage. Drogba and Lampard mean more than 50 per cent of the goals Chelsea score and they're not playing."

For the Norwegian side the result was a serious achievement. They beat Milan 2-1 in 1996 and Borussia Dortmund 3-0 three years later. The champions of Norway, they have played in the Champions League 11 seasons out of the last 13 years.

Their manager Knut Torum said that he believed his team could score at a set piece – as they did in the 24th minute.

"If the top players are a little bit down in their heads, it shows in the box at set-pieces," he said.