Bremen, who hold a two-point advantage over the European champions, produced a surprise win over group leaders Chelsea on Wednesday and need only one point in Nou Camp on December 5th to qualify.

"In the last match against Werder we have no other option left than to win," Rijkaard told reporters after Barcelona beat minnows Levski Sofia on Wednesday.

"It is going to be a difficult game, but I am optimistic that we will come out on top and reach the last 16 of Europe's premier club competition," he added.

Rijkaard said his optimism was derived from the multitude of talent his team has in its ranks.

"We have many versatile players who are very good with the ball at their feet and capable of rising to the occasion. That's what I will ask them to do against Bremen," said the Dutch coach.

Goals from Ludovic Giuly goal and Andres Iniesta secured the win for the Catalan giants in Bulgaria, but Rijkaard was adamant his team didn't play their usual game.

"It wasn't a great game of football from us but we were patient and got the result we needed. Levski fought back well after conceding an early goal and never made it easy for us.

"It is sometimes difficult to play against sides like them with the vociferous home crowd getting behind their team but the second goal was vital and took the pressure off," he added.