Bayern striker Miroslav Klose has recovered from a stomach virus, and is in contention for a place in the starting line up, but Mark van Bommel and Holger Badstuber are both suspended.
Jean Makoun, Mathieu Bodmer and Jean-Alain Boumsong are all injured for the French side, who have seven players one booking away from a suspension.
- Rumours: Ribery in sex scandal
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This will be Lyon's first appearance in a Champions League semi-final, and Bayern coach Louis van Gaal will hope his team can take advantage of their opponents' inexperience.
However, Bayern have hardly been regulars at this stage of the competition in recent years; this is their first semi-final since 2001, when they went on to lift the trophy. Lyon did beat them that year though, 3-0 at the Stade Gerland.
After a shaky start at the Allianz Arena, Van Gaal has steadied the ship impressively. Bayern are chasing a treble of league, cup and Champions League, and are in scintillating form after destroying Hannover 7-0 at the weekend, with Arjen Robben helping himself to a hat-trick.
Bayern full-back Phillip Lahm is expecting a tough game though: "They [Lyon] are very strong. We will try not to concede a goal. 1-0 would be good, 2-0 would be better," he said.
But Lyon will prove a tough nut to crack; they have the tightest defence of any of the teams in the last four, having conceded just six goals in the competition so far.
Lyon coach Claude Puel said: "The Germans are always dangerous in big matches. We know what to expect."
All eyes will be on Bayern's French playmaker Franck Ribery this evening, after being questioned over the weekend about his involvement with a teenage prostitute in a nightclub.
- Robbie Blakeley
Source: DSG
