Hayden Penn returned to the US today in order to get his left elbow cleaned out. While Penn most likely won't be able to throw for about a month, he probably return to Japan after about 20 days.
In other team injury-related news:
Tae-Kyun Kim was taken off the active roster today with a sprain in his right wrist (the pain wasn't going). Lotte is hopeful he'll be able to return in 10 days.