Hamburg  - Bayern Munich head into Saturday's Bundesliga clash against Werder Bremen needing to step up a gear if new coach Louis van Gaal isn't to start coming under pressure just two games into the new season.

A lucky 1-1 draw against TSG Hoffenheim in their Bundesliga opener last weekend has made clear to van Gaal that he has a lot of work to do if Bayern are to live up to the mantle of title favourites.

Despite the demand for immediate success, Van Gaal has made clear he won't risk recovering midfielder Franck Ribery from the start although Miroslav Klose is fit as evidenced by his 45th goal for Germany in a midweek World Cup qualifier against Azerbaijan in Baku.

"He is still in the process of rehabilitation," van Gaal said of Ribery in an interview with Kicker magazine. "He won't start but we might give him 20 minutes."

Like Klose, Ribery missed the draw with Hoffenheim but the 26- year-old returned to action with France on Wednesday when he played for 25 minutes in his country's 1-0 win over the Faroe Islands.

While van Gaal's Bayern struggled to find their feet on the opening day, German Coach of the Year Felix Magath hit the ground running with new club Schalke 04 thanks to a 2-1 win at promoted Nuremberg.

Former Bayern coach Magath led VfL Wolfsburg to their first Bundesliga title last season but is now looking to give Schalke a first national title since 1958.

Next up for Schalke Sunday are VfL Bochum, who came from three goals down to 10-man Borussia Moenchengladbach to salvage a draw. Gladbach are also in action Sunday when they take on Hertha Berlin.

Champions Wolfsburg got their defence off to the perfect start with a comfortable 2-0 win over VfB Stuttgart and coach Armin Veh will be confident of his side maintaining their 100-per-cent record Saturday away to Cologne.

Stuttgart welcome newly-promoted neighbours Freiburg while SV Hamburg entertain Borussia Dortmund.

Bayer Leverkusen return to their newly renovated BayArena to take on Hoffenheim following the completion of a 70-million-euro (99- million-dollar) upgrade that began in December 2007.

The new stadium, which has a capacity of 30,000 compared to the old one's 22,500, will be greeted warmly by coach Bruno Labbadia whose team only won one of eight home matches played in the second half of last season in Dusseldorf.

"I think this stadium is beautiful and fantastic," said club CEO Wolfgang Holzhäuser. "We've toiled on this for 20 months and have made something great."

In other matches, Eintracht Frankfurt play Nuremberg and Hanover 96 welcome Mainz 05. (dpa)