Chelsea's Frank Lampard [Images] believes his team still have a lot of work to do against Bayern Munich in the second leg of their Champions League quarter-final.

The England [Images] midfielder scored twice as the London [Images] side beat their German visitors 4-2 at Stamford Bridge but Lampard knows they will have to work hard in Tuesday's return.

"They are very strong, well organised and have got world class players and Michael Ballack [Images] in the end got a penalty and scored and he will be a big threat out there.

"We saw what Bayern Munich did to Arsenal [Images] in Germany [Images]. It's definitely not over."

Chelsea's London rivals Arsenal lost 3-1 to Bayern in the last round before going out 3-2 on aggregate.

Bayern coach Felix Magath, who was without injured strikers Roy Makaay and Claudio Pizarro and suspended Martin Demichelis, told German television his side struggled to cope with Chelsea's powerful Ivory Coast striker Didier Drogba [Images].

"We had a lot of problems with Drogba -- we never managed to get him under control. Normally we're strong in defence and I don't think something like this will happen again.

"If we have Roy Makaay, Claudio Pizarro and Martin Demichelis back in the side I'm confident we can do it."

Despite a superb performance by Lampard, whose second-half double came after an early Joe Cole strike and a late goal from Drogba, the midfielder was not entirely happy.

LAMPARD DISAPPOINTED

"At the moment I'm disappointed because of the last minute [penalty by Ballack]. 4-1 would be a great lead to take there, 4-2 still is but obviously we're disappointed."

Ballack fell inside the area after the slightest touch on his left arm by Portugal defender Ricardo Carvalho.

"He [Carvalho] might have got a touch on him [Ballack], I don't know, but he [Ballack] was definitely looking for it. Two goals is a good lead but three would be better.

"We are confident we can score goals anywhere in Europe but the game is by no means over. We were solid, they were tight in midfield but we got the goals we deserved."

Asked what the absent Jose Mourinho had said to the players earlier on Wednesday before observing the first game of his two-match UEFA [Images] touchline ban, Lampard replied: "It was just very normal. We had meetings and he talked about them [Bayern] and told us to go out and do our stuff."

Chelsea's assistant managers Baltemar Brito and Steve Clarke were in charge of team affairs on the bench and Brito said they were given some leeway to influence events during the game.

"Before the match Jose had predicted what was going to happen, had predicted the strategies, leaving parts open for us to make decisions during the game," Brito told Sky Sports.

However, he is not happy with the decision by European soccer's governing body to ban the Chelsea manager.

"We are not happy that Jose won't be with us in the second leg, what happened to him was an injustice.

"But the players showed their ability today to beat any team. They are magnificent players. We beat Barcelona and put four goals past Bayern. But as far as Jose [is concerned] we're not very happy."

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