By reaching the third round at the 2008 Olympics[3] and the final of 2009 Denmark Open, one of premier tournament competition series BWF World Superseries, Zwiebler is considered as Germany's top badminton player of all time.

After an operation in late 2006 and six months of rehabilitation and fitness training with a total of one and a half year absence, he started to chase after the Olympic qualification.

At 2009 Denmark Open, Zwiebler defeated the number four seeded Malaysia's Wong Choong Hann in the first round in three sets.

In the semifinals, he finally won over the reigning World Cup bronze medalist and runner-up of 2007 Indonesia's Sony Dwi Kuncoro in three sets.

[5] Later that year, he gained a bronze medal at the European Championships after losing to Peter Gade in the semifinals in a thrilling match 21–18, 12–21, 17–21.