Bayern Munich will be without stars Ivica Olic and Arjen Robben for Friday night's Bundesliga opener as they begin their quest for their 23rd German league title - and target the treble.

Bayern host Wolfsburg at Munich's Allianz Arena without Dutch winger Robben, who is recovering from the leg injury he picked up just before the World Cup, while Croatia's Olic is struggling with a knee injury.

With Olic out, Germany striker Miroslav Klose is expected to start as the lone striker for Bayern, with Mario Gomez on the bench.

Bayern captain Mark van Bommel faces a race against time to be fit to face Wolfsburg as he also has a muscular injury. If he fails to make it, Danijel Pranjic will take over in midfield.

Only defeat in last season's Champions League final by Inter Milan prevented Bayern from winning the treble and van Bommel says the goal for this season is to add Europe's top domestic title to the league and cup double.

"That is the great challenge for this season," said van Bommel.

Wolfsburg will have Germany defender Arne Friedrich in the side after his transfer from relegated Hertha Berlin, while ex-England coach Steve McClaren becomes the Bundesliga's first English manager.

"Bayern have a great squad with many world-class players," admitted McClaren.

"What could be better in the first game than to take on the champions?

"It will be a great evening."

The Wolves will be without Swiss goalkeeper Diego Benaglio, whose wife is expecting the couple's first child.

McClaren is still trying to strengthen his Wolfsburg squad and is reported to be interested in signing both Liverpool's Ryan Babel and Brazilian playmaker Diego from Juventus.

Two of Bayern's main title rivals clash on Saturday night, when last season's runners-up Schalke are at Hamburg.

There are question marks over Schalke centre-back Christoph Metzelder, who has an upper groin injury, while coach Felix Magath may give veteran Spain striker Raul more time to get match fit.

Hamburg have a few injury worries, namely Germany defender Dennis Aogo, who has a trapped sciatic nerve.

South Korean striker Son Heung-Min is also out with a foot injury for Hamburg.

Fresh from their 3-1 win over Sampdoria on Wednesday night in the Champions League play-off round, Werder Bremen are at Hoffenheim on Saturday but without Germany playmaker Mesut Ozil, who signed for Real Madrid this week.

Nigerian striker Chinedu Obasi misses the game with a stress fracture of the shin for Hoffenheim.

Stuttgart are at Mainz on Sunday looking to open their Bundesliga campaign with a win.

Tunisian striker Sami Allagui is likely to start, having joined Mainz during the off season, while Stuttgart have Christian Traesch in their side after he missed out on a World Cup place with Germany due to an ankle injury.

Germany star Michael Ballack is expected to start for his new club Bayer Leverkusen against Borussia Dortmund on Sunday night as he works his way back to full fitness after the ankle injury that kept him out of the World Cup.

Bayer fell away at the end of last season, having led the table for most of the year, and coach Jupp Heynckes will want no repeat from his side this term.