The 25-year-old played for the first time since 2012 when he featured for an hour in the German champions' 3-0 friendly win over the Red Baroons fan club on Friday.
Badstuber ruptured his anterior cruciate ligament against Borussia Dortmund in December 2012 and suffered a recurrence of the injury in May last year.
Despite enduring a prolonged spell on the sidelines, Badstuber was always confident he would return and claims he is now playing pain free.
"No, there was no doubt [that I might not return from injury]. I always knew I'd get a chance here, playing free of any pain. I always looked forward and was very focused," he said.
"I don't make any demands [on my knee]. I enjoy every training session. Obviously I want to improve.
"I'm feeling good. If I look back over the last year, in comparison with today, I have made such big steps.
"I hope it will continue that way and then we will see what happens. It was a great feeling to finally be on the pitch with the team again.
"It is very useful to have match practice, because it is certainly not like usual training. I'm enjoying every second and I don't have any pain at all. I will continue to work hard and then we will see what happens."
