Even top professionals cannot stay on Tygem 9-dan level!

Well known Korean 9p Seo Nunwook (joonki on Tygem) went down from 9d
to 8d on Tygem few days ago.
In the past he was one of the best Korean pros - probably number 3, after Cho Hunhyun and Seo Bongsu.
He won several titles and was a challenger lot of times.

Few months ago he was one of the best 9-dans in Tygem ranking system,
but recently he lost lot of games straight.
His Go is very fast and he makes lot of mistakes, it seems.  He played
more than 12000 games on Tygem! And when you play so many games, it's
hard to show the high percentage of victories.
On Tygem he plays top 9-dans a lot, including famous 9-dans from
China, so maybe it's not a big sensation. I believe that most Chinese
young professionals are already stronger than old Korean pros.

We will see, can he return back to 9-dan or not!