"He is feeling much better," coach Pep Guardiola said of the Germany international who was rested for the weekend's Bundesliga win over Hanover 96.
Expectations are high in the Bavarian capital after Bayern's stunning treble-winning campaign last season under Jupp Heynckes, but Guardiola, who took over in the close season, said any talk of defending their European crown was premature.
"It is far too early to talk about this," Guardiola told reporters. "First all of we want to survive the group stage and qualify for the knockout rounds.
"Then we can see what happens if we are into the last 16 or semi-finals. But it is too early to talk about it today."
The Spaniard, winner of the European title both as player and coach of Barcelona, is under immense pressure to deliver silverware but his Bayern side have been accused of being lethargic by club sports director Matthias Sammer despite a fourth win in five league games on Saturday.
They are in second place, two points behind leaders Borussia Dortmund.
"We played lethargically at times, we played football without emotion, we worked as if we were following rules," Sammer said on Sunday. "We must get out of our comfort zone."
Sammer's outburst caused a stir in Germany, especially as Bayern have yet to lose in the Bundesliga and the German Cup this season while stretching their unbeaten league run to 30 games with their 2-0 win over Hanover 96.
However, Guardiola said Sammer's criticism was not out of order.
"I instantly understood how club bosses support this team," Guardiola said. "Matthias is very emotional like me. He is the most important person in the changing rooms and one of the most important at the club.
"That is the culture in Germany. People within the club can speak their mind and they can do it to the media. If that happens in Spain, well then there is a big problem. We do not know it like that. I have to adapt to that."
Guardiola warned CSKA players would be very fit with their season starting earlier. The Russian champions are unbeaten after eight league games.
"It will be complicated. Physically they are a very strong team," said Guardiola. "At this moment CSKA are very strong. In my experience they are not so much after their winter break in the spring, but now they are strong."